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ContentPreparatory

Courses1. Sem. 2. Sem. 3. Sem. 4. Sem. 5. Sem. 6. Sem.

Laboratory Experiments

Basics in General,

Analytical, Organic and Inorganic Chemistry

(Chapter 2)***

General Chemistry (Chapter 3)

Analytical Chemistry (Chapter 4)

Inorganic Chemistry (Chapter 7)

Organic Chemistry (Chapter 8)

Technical Chemistry (Chapter 9)

Physical Chemistry (Chapter 6)

Biochemistry (Chapter 10)

Lecture,Tutorial,Experiments


Inorganic Chemistry (Chapter 7)


Biochemistry (Chapter 10)

Spectroscopy (Chapter 5)

Physical Chemistry

(Chapter 6)

Elective Subject Microbiology **

e.g. Biotechnology, Material Chemistry

(Chapter 10)

Interdis.Subjekt

General Physics *

Electro- chemistry

(Chapter 6.6)

Molecular Analytics (NMR) and Spectroscopy (Chapter 5)

TheoreticalCourses Mathematics

Statistical Thermo- dynamics

Theoretical Chemistry

BachelorThesis Bachelor Thesis

Content 1. Sem. 2. Sem. 3. Sem. 4. Sem. 5. Sem. 6. Sem.

Laboratory Experiments General Biology **


Spectroscopy (Chapter 5)

Pharmacognosy Microscopy of

medical plants **

Clinical Chemistry***


Inorganic Chemistry(Chapter 7)

Analytical Chemistry(Chapter 4)

Human Physiology ***

Microbiology **

Lecture,Tutorial,Experiments

General Physics *Physical Chemistry:

Gas Laws, Viscosity, Thermodynamics (Chapter 6)

Biochemistry (Chapter 10.1)

Chromatography

(Chapter 4.3)Human

Physiology ***Histology *** Pharmaceutical Technology

Elective Subject

Disposal, Environment Protection

(Chapter 9.3)

Immunologye.g. Biotechnology

(Chapter 10.2)

Theoretical Courses Mathematics Pharmacokinetics Pharmacognosy Pathophysiology

Pharmaceutical Engineering

BachelorThesis Bachelor

Thesis

PHYWE experiments have been matched to the curricula of more than 30 selected universitiesworldwide. The interaction between PHYWE’s experiments and the supporting content ofexperimental lectures and lab course has led to the creation of a teaching package that is highlyrelevant to the taught curriculum worldwide.

Pharmacy Bachelor of Science course - Reference Example

Pharmacy is one of the most multidisciplinary subjects taught in natural sciences. The firstsemesters or introductory courses cover general topics in physics, biology and medicine.Pharmaceutical chemistry includes the classical main topics of chemistry: Inorganic, Organic,Analytical Chemistry, Spectroscopy and Biochemistry with reference to pharmaceutical topics.

PHYWE Experiments available in this catalogue

Please refer to TESS expert Physics catalogue* *** Also refer to TESS beginner/advanced brochure** Please refer to TESS expert Biology catalogue

PHYWE Experiments available in this catalogue

TESS expert Laboratory Experiments Physics TESS expert Laboratory Experiments PhysicsTESS expert Laboratory Experiments Biology TESS expert Laboratory Experiments BiologyTESS beginner / advanced brochure TESS expert Laboratory Experiments Medicine

Please refer to TESS expert Physics catalogue* *** Please refer to TESS expert Medicine catalogue** Please refer to TESS expert Biology catalogue

Chemistry Bachelor of Science course - Reference Example

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AMERICAS

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TESS expert ChemistryTESS expert Chemistry11 Table of ContentsTable of Contents 22

22 Preparatory CoursePreparatory Course 1111

33 General ChemistryGeneral Chemistry 1515

44 Analytical ChemistryAnalytical Chemistry 4545

55 SpectroscopySpectroscopy 5555

66 Physical ChemistryPhysical Chemistry 6767

77 Inorganic ChemistryInorganic Chemistry 133133

88 Organic ChemistryOrganic Chemistry 153153

99 Industrial ChemistryIndustrial Chemistry 167167

1010 Biochemistry and BiotechnologyBiochemistry and Biotechnology 183183

1111 About PHYWEAbout PHYWE 195195

1212 IndicesIndices 209209

TESS expert ChemistryTESS expert Chemistry

PHYWE Systeme GmbH & Co. KG · www.phywe.comwww.phywe.com

1

1 Table of Contents1 Table of Contents


2

2 Preparatory Course

2.22.2 General ChemistryGeneral Chemistry

15300-88 TESS advanced Chemistry set GeneralChemistry

13

13300-10 TESS advanced General Chemistry, con-sumables and chemicals for 10 groups

13

13431-88 TESS advanced General Chemistry, neces-sary accessories for 1 group

13

2.32.3 Inorganic ChemistryInorganic Chemistry

15301-88 TESS advanced Chemistry set InorganicChemistry

14

13301-10 TESS advanced Inorganic Chemistry, con-sumables and chemicals for 10 groups

14

13433-88 TESS advanced Inorganic Chemistry, ne-cessary Accessories for 1 group

14

3 General Chemistry

3.13.1 EquilibriaEquilibria

P3031001 Complex formation equilibrium / com-plex formation constant

16

P3030960 Dissociation equilibrium (with Cobra4) 17

P3030862 Solubility product (with Cobra4) 18

P3030701 Distribution equilibrium 18

P3031101 Dissociation constants 18

3.23.2 Molar MassMolar Mass

P3010401 Determination of molar mass using theideal gas law

19

P3010501 Determination of the molecular mass ofa liquid

20

P3021900 Determination of molar masses via ameasurement of the boiling point eleva-tion (ebullioscopy)

21

P3022000 Determination of molar masses via ameasurement of the freezing point de-pression (cryoscopy)

22

P1309400 Determination of the molar masses ofmetals

23

3.33.3 Acids and BasesAcids and Bases

P3061660 Titration curves and buffering capacity(with Cobra4)

24

P3020811 Determination of the enthalpy of neut-ralisation (with Cobra3)

25


25

P1310100 Chemical fountain 26

P3121260 Titration of a polyvalent acid with astrong base (with Cobra4)

27

P3121360 Titration of a weak organic acid with so-dium hydroxide (with Cobra4)

27

P3121460 Titration of a weak base (ammonia) witha strong acid (with Cobra4)

27

3.43.4 Solutions and MixturesSolutions and Mixtures

P3030501 Solubility diagram of two partially mis-cible liquids

28

P3030601 Miscibility gap in a ternary system 29

P4100760 The origin of acid rain (with Cobra4) 30

P3061062 Concentration cells without transport:Determination of the solubility productsof silver halides (with Cobra4)

31

P1135700 Osmosis - dependence of the osmoticpressure on the concentration

32

P3030862 Solubility product (with Cobra4) 33

P3030960 Dissociation equilibrium (with Cobra4) 34

P3031101 Dissociation constants 35

P3021001 Boiling point elevation 36

P3021101 Freezing point depression 36

3.53.5 Redox ReactionsRedox Reactions

P3110600 Redox reactions between metals andmetal oxides (thermite process)

37

P3100300 Reduction - reducing agents - redox pro-cess

38

P3100400 Reduction of lead oxide 39

P3110400 Sulphur trioxide - the sulphuric acidcontact process

40

P3110500 Preparation of iron from oxidic ores(blast furnace process)

40

P3121060 Volumetric redox titration: Cerimetry(with Cobra4)

40

3.63.6 StoichiometryStoichiometry

P3110900 The empirical formula of methane, eth-ane and propane

41

P3111000 Avogadro's law 42

P3121660 Briggs-Rauscher Reaction (with Cobra4) 43

P1309400 Determination of the molar masses ofmetals

44

4 Analytical Chemistry

4.14.1 TitrationTitration

P3060760 Conductivity titration (with Cobra4) 46

P3061760 Potentiometric pH titration (phosphoricacid in soft drinks) (with Cobra4)

47

Table of ContentsTable of Contents


3

P3121060 Volumetric redox titration: Cerimetry(with Cobra4)

48

P3061460 Precipitation titration (with Cobra4) 49

P3061660 Titration curves and buffering capacity(with Cobra4)

50

4.24.2 ElectrogravimetryElectrogravimetry

P3062201 Electrogravimetric determination of cop-per

51

4.34.3 ChromatographyChromatography

P3120400 Chromatographic separation processes:thin layer chromatography

52

P3031760 Chromatographic separation processes:Gas chromatography (with Cobra4)

53

P3120300 Column chromatography - separation ofleaf pigments

54

5 Spectroscopy

5.15.1 X-ray Fluorescence AnalysisX-ray Fluorescence Analysis

P2544701 Qualitative X-ray fluorescence analysis ofpowder samples

56

P2545001 Quantitative X-ray fluorescence analysisof alloyed materials

57

P2545101 Quantitative X-ray fluorescence analysisof solutions

58

P2544501 Qualitative X-ray fluorescence spectro-scopy of metals - Moseley's law

58

P2544601 Qualitative X-ray fluorescence analysis ofalloyed materials

58

5.25.2 Nuclear Magnetic ResonanceNuclear Magnetic Resonance

09500-99 Compact MRT 59

P5942100 Fundamental principles of Nuclear Mag-netic Resonance (NMR)

62

P5942200 Relaxation times in Nuclear MagneticResonance

63

P2511205 Model experiment NMR / ESR 64

5.35.3 Photometry and PhotochemistryPhotometry and Photochemistry

35610-88 Measurespec spectrometer with cuvetteholder and light source

65

P3070101 Absorption of light (UV-VIS spectroscopy) 66

P3070301 Excitation of molecules 66

P3070401 Absorption spectra and pKa values of p-methoxyphenol

66

6 Physical Chemistry

6.16.1 Gas LawsGas Laws

P3011160 Gay-Lussac's law (with Cobra4) 70

P3011260 Amontons' law (with Cobra4) 71

P3011360 Boyle's law (with Cobra4) 72

P3031401 Law of integer ratio of volumes accordingto Gay-Lussac's law of chemical volumes

73

P2320400 Thermal equation of state and criticalpoint

73

01196-12 Handbook Glass Jacket System 74

6.26.2 Kinetic TheoryKinetic Theory

P2320300 Maxwellian velocity distribution 75

P3010301 Diffusion in gases: The diffusion coeffi-cient of bromine in air

76

6.36.3 ViscosityViscosity

P2140300 Viscosity of Newtonian and non-Newto-nian liquids (rotary viscometer)

77

P2140400 Viscosity measurement with the fallingball viscometer

78

P3010601 Determining the molecular weight of apolymer from intrinsic viscosity meas-urements

79

6.46.4 Thermochemistry / CalorimetryThermochemistry / Calorimetry

P3020260 Adiabatic coefficient of gases - Flam-mersfeld oscillator

80

P2320201 Heat capacity of gases 81

P3020411 Determination of the enthalpy of vapor-isation of liquids (with Cobra3)

82

P3020460 Determination of the enthalpy of vapor-isation of liquids (with Cobra4)

82

P3020501 Partial molar volumes 83

P3020611 Determination of the mixing enthalpy ofbinary fluid mixtures (with Cobra3)

84

P3020660 Determination of the mixing enthalpy ofbinary fluid mixtures (with Cobra4)

84

P3020711 Determination of the hydration enthalpyof an electrolyte (solution enthalpy)(with Cobra3)

85


85

P3020760 Determination of the hydration enthalpyof an electrolyte (solution enthalpy)(with Cobra4)

85

P3020911 Determination of the melting enthalpyof a pure substance (with Cobra3)

86

P3020960 Determination of the melting enthalpyof a pure substance (with Cobra4)

86



4

P3021401 Determination of the enthalpy of com-bustion with a calorimetric bomb

87

P3021501 Determination of the heat of formationof water

88

P3021601 Determination of the heat of formationfor CO2 and CO (Hess' law)

89

P3021701 Determination of the heating value offuel oil and of the calorific value of oliveoil

90

P2310100 Thermal expansion in solids and liquids 91

P3040801 Adsorption isotherms 92

6.56.5 Chemical KineticsChemical Kinetics

P3050101 Saponification rate of tert-butyl chloride 93

P3051101 Dependence of the reaction velocity onthe temperature (acetic acid - magnesi-um)

94

P3050201 Reaction rate and activation energy ofthe acid hydrolysis of ethyl acetate

95

P3050301 Kinetics of the inversion of saccharose 96

P3050760 Halogen exchange rate (with Cobra4) 97

P3050860 Conductometric measurement of the sa-ponification of esters (with Cobra4)

98

P3121660 Briggs-Rauscher Reaction (with Cobra4) 99

P4120360 Determination of the Michaelis constant(with Cobra4)

100

P4120560 Enzyme inhibition (poisoning of en-zymes) (with Cobra4)

100

6.66.6 Electro ChemistryElectro Chemistry

P3060111 Charge transport in solids (with Cobra3) 101

P3060160 Charge transport in solids (with Cobra4) 101

P3060260 Charge transport in liquids (with Cobra4) 102

P3060301 Ion migration velocity 103

P3060401 Transference numbers 104

P3060560 Temperature dependence of conductivity(with Cobra4)

105

P3060660 Conductivity of strong and weak electro-lytes (with Cobra4)

106

P3060862 Determination of the activity coefficientby a conductivity measurement (with Co-bra4)

107

P3060962 Nernst equation (with Cobra4) 108

P3061101 Determination of diffusion potentials 109

P3061262 Temperature dependence of the electro-motive force (with Cobra4)

110

P3061562 pH measurement (with Cobra4) 111

P3061811 Electrode kinetics: The hydrogen overpo-tential of metals (with Cobra3)

112

P3061860 Electrode kinetics: The hydrogen overpo-tential of metals (with Cobra4)

112

P3062101 Determination of Faraday's constant 113

P2411100 Characteristic curve and efficiency of aPEM fuel cell and a PEM electrolyser

114

P3062201 Electrogravimetric determination of cop-per

115

P1268360 Voltage of a concentration cell (with Co-bra4)

116

P1282360 Electrochemical series of metals (withCobra4)

116

6.76.7 Phase EquilibriumPhase Equilibrium

P3021001 Boiling point elevation 117

P3021101 Freezing point depression 118

P3030401 Boiling point diagram of a binary mix-ture

119

P1273460 Heat of fusion of sodium thiosulphate(with Cobra4)

120

P3031360 Melting diagram of a binary mixture(with Cobra4 )

121

P3011400 Condensation of gases through an in-crease of pressure and through cooling

122

P3031900 Sublimation and solubility of iodine 123

P3031251 Steam distillation 124

P3031501 Rectification - the number of theoreticaltrays in a distillation column

124

P3031640 Fractional distillation with the bubbletray column (with Cobra3)

124

6.86.8 Atomic Structures and PropertiesAtomic Structures and Properties

P2510315 Franck-Hertz experiment with a Ne-tube 125

P2510311 Franck-Hertz experiment with a Hg-tube 125

P2510600 Fine structure: One and two electronspectra

126

P2510700 Balmer series/ determination of Ry-dberg's constant

127

P2510200 Specific charge of the electron e/m 128

P2511006 Zeeman effect with a variable magneticsystem

129

P2511111 Stern-Gerlach experiment with a stepmotor and interface

130

P5942100 Basic principles in Nuclear Magnetic Res-onance (NMR)

131

P2210300 Dispersion and resolving power of aprism and a grating spectroscope

132

7 Inorganic Chemistry

7.17.1 Chemistry of MetalsChemistry of Metals


134

P1310500 Molten-salt electrolysis 135

P1025200 Oxidation of metals 135



5

P3100100 Effects of acids on metals 135

P3100400 Reduction of lead oxide 136

P1026800 Reduction of silver oxide 136

P1026900 Reduction of copper oxide 136

7.27.2 Coordination ChemistryCoordination Chemistry

P3031001 Complex formation equilibrium / com-plex formation constant

137

7.37.3 Organometallic ChemistryOrganometallic Chemistry

P3101000 Haloalkanes: Grignard reagent 138

P3101100 Haloalkanes: Wurtz reaction - lithiumorganyls

139

7.47.4 Solid-state Chemistry and CristallographySolid-state Chemistry and Cristallography

P2541301 Examination of the structure of NaClmonocrystals with different orientations

143

P2541401 X-ray investigation of cubic crystal struc-tures / Debye- Scherrer powder method

144

P2541501 X-ray investigation of hexagonal crystalstructures / Debye-Scherrer powdermethod

144

P2541602 X-ray investigation of crystal structures/ Laue method with digital X-ray imagesensor (XRIS)

145

P2541601 X-ray investigation of crystal structures /Laue method

145

P2542101 Debye-Scherrer diffraction patterns ofpowder samples with three cubic Bravaislattices (Bragg-Brentano-geometry)

146

P2542201 Debye-Scherrer diffractions pattern ofpowder samples with a diamond struc-ture (according to Bragg-Brentano)

146

P2542301 Debye-Scherrer diffraction patterns ofpowder samples with a hexagonal latticestructure

146

P2542401 Debye-Scherrer diffraction patterns ofpowder samples with a tetragonal latticestructure

146

P2542501 Debye-Scherrer diffraction patterns witha cubic powder sample

146

P2542201 Debye-Scherrer diffractions pattern ofpowder samples with a diamond struc-ture (according to Bragg-Brentano)

147

P2532000 Atomic Resolution of the graphite sur-face by STM (Scanning Tunneling Micro-scope)

148

09600-99 Compact-Scanning Tunneling Microscope(STM)

149

09613-00 Set samples nanomorphology, for Com-pact Scanning Tunneling Microscope(STM)

149

P2538000 Basic methods in imaging of micro andnanostructures with atomic force micro-scopy (AFM)

150

P2538400 Imaging of biological and medical microand nanostructure with atomic force mi-croscopy (AFM)

150

09700-99 Compact-Atomic Force Microscope (AFM) 151

7.57.5 LiteratureLiterature

01200-02 Handbook Physics X-Ray Experiments 152

8 Organic Chemistry

8.18.1 Organic SynthesisOrganic Synthesis

P3101100 Haloalkanes: Wurtz reaction - lithiumorganyls

154

P3101300 Toluene: Bromination in the nucleus 155

P3101400 Aldehydes - reactions with ammonia 156

P3101500 Preparation of p-toluenesulfonic acid 157

P3101600 Cannizzaro reaction and reaction of ben-zaldehyde with ethylene glycol

158

P3101000 Haloalkanes: Grignard reagent 159

P3120500 Electrophilic addition of bromine toacetylene (ethyne)

159

8.28.2 Distillation, PurificationDistillation, Purification


160


160

P3031251 Steam distillation 161

P1308962 Distillation - determination of the alco-hol content of wine (with Cobra4)

162

P3120100 Separation of mixtures of liquids and ofsolutions by extraction, stirring, centri-fugation

163

P3120200 Quantitative determination of fat / Soxh-let extraction

164

P3120400 Chromatographic separation processes:Thin layer chromatography

165

P3031760 Chromatographic separation processes:Gas chromatography (with Cobra4)

165

P3120300 Column chromatography - separation ofleaf pigments

165

01837-02 TESS Chemistry manual Organic Chemistry 166

9 Industrial Chemistry

9.19.1 GasesGases

P3110100 Obtaining nitrogen oxides by burning air 168

P3110200 Ammonia preparation from the elements(Haber-Bosch process)

169



6

P3110300 Combustion of ammonia to produce ni-trogen dioxide - Ostwald process

170

P3110400 Sulphur trioxide - the sulphuric acidcontact process

171

9.29.2 SaltsSalts

P3110700 Salts of sulphuric acid - sulphates 172

P1310500 Molten-salt electrolysis 173

9.39.3 Disposal, Environment ProtectionDisposal, Environment Protection

P1310000 Model experiment on the desulphurisa-tion of flue gas

174

P1309200 Electrostatic flue gas cleaning 175

9.49.4 PetrochemistryPetrochemistry


176


176


177

P3110800 Cracking of hydrocarbons 178

P3021701 Determination of the heating value offuel oil and of the calorific value of oliveoil

179

9.59.5 MetallurgyMetallurgy

P5510100 Metallographic sample preparation -grinding and polishing

180

P5510200 Metallographic sample preparation -chemical etching

181

P3110500 Preparation of iron from oxidic ores(blast furnace process)

182


182

10 Biochemistry and Biotechnology

10.110.1 BiochemistryBiochemistry

P4120160 Determination of the isoelectric point ofan amino acid (glycine) (with Cobra4)

184

P4120360 Determination of the Michaelis constant(with Cobra4)

185

P4120460 Substrate inhibition of enzymes (withCobra4)

186

P4120560 Enzyme inhibition (poisoning of en-zymes) (with Cobra4)

187

P4120660 The enzymatic activity of catalase (withCobra4)

187

10.210.2 BiotechnologyBiotechnology

P1313600 Fermentation of molasse to ethanol withyeast

188

P1313762 Microbial synthesis of ethanol by Zy-momonas mobilis subsp. mobilis (withCobra4)

189

P1313862 Production of amino acids by ferment-ation of Corynebacterium glutamicum(with Cobra4)

190

P1313962 Bacteria and mining - microbial extrac-tion of ore by Thiobacillus ferrooxidiansand thiooxidans (with Cobra4)

191

P1314000 Immobilised cells in the service of bio-technology - microbial synthesis of acet-ic acid with Acetobacter aceti

192

10.310.3 LiteratureLiterature

01855-02 Complete Experiments Chemistry/Bio-technology

193

01331-02 Demo advanced Biology Manual Cobra4Biochemistry & plant physiology

194



7

1 Table of Contents1 Table of Contents1.2 How to use


8

1 Table of Contents1 Table of Contents1.2 How to use


9

1 Table of Contents1 Table of Contents1.3 Cooperations


10

121213131414

Preparatory CoursePreparatory Course2.12.1 OverviewOverview2.22.2 General ChemistryGeneral Chemistry2.32.3 Inorganic ChemistryInorganic Chemistry

2 Preparatory Course2 Preparatory Course


11

2 Preparatory Course2 Preparatory Course2.1 Overview


12

Function and ApplicationsFunction and Applications

Set for the realization of 25 student experiments on the topics:

▪ Properties of materials (5 experiments)▪ Mixtures (2 experiments)▪ Separation of mixtures (4 experiments)▪ Chemical reactions (2 experiments)▪ Test reactions (3 experiments)▪ Particle model (4 experiments)▪ Chemical bonds (5 experiments)

BenefitsBenefits

▪ Complete device set for an easy realization of the experiments▪ Stable storage system: easy to store (stackable), fast control on

completeness (foam inserts)▪ The use of the software minimizes preparation time and facil-

itates individual learning speeds

List of topics, General ChemistryList of topics, General Chemistry

1. Properties of matter1. Properties of matter- Hardness, colour, magnetisability, water solubility- Combustibility, melting point- Boiling point; Sublimation; Density determination2. Mixtures and mixture separation2. Mixtures and mixture separation- Properties of mixtures; Liquid mixtures3. Mixture separation3. Mixture separation- Evaporation; Filtration, magnetic separation- Extraction; Chromatography4. Chemical reactions4. Chemical reactions- Comparison of a physical process and a chemical reaction- Reaction of copper and sulphur5. Test reactions5. Test reactions- The detection of oxygen; The detection of hydrogen;

- The detection of nitrogen6. Particle model6. Particle model- Degradation of water by reducing agents- Dissolution processes in liquids- Dissolution of salts; Crystallisation7. Chemical bonds7. Chemical bonds- Test confirming the migration of ions by means ofindicator paper- Periodic system; Dipolar properties- Melting point lowering/ boiling point elevation- Behaviour of salts with regard to solvents of different po-larities

Additionally required materialAdditionally required material

15300-8815300-88TESS advanced Chemistry set General ChemistryTESS advanced Chemistry set General Chemistry

Sublimation of benzoic acid.

TESS advanced General Chemistry, consumables andTESS advanced General Chemistry, consumables andchemicals for 10 groupschemicals for 10 groups

13300-1013300-10

TESS advanced General Chemistry, necessary accessories forTESS advanced General Chemistry, necessary accessories for1 group1 group

13431-8813431-88

2 Preparatory Course2 Preparatory Course2.2 General Chemistry


13


Set for the realization of 34 student experiments on the topics:

▪ Metals (3 experiments); Air and other gases (12 experiments)▪ Water - components of water and water purification (11 ex-

periments)▪ Building material (3 experiments); Fertilizer (4 experiments)▪ Glas manufacture (1 experiment)

BenefitsBenefits

▪ Complete device set for an easy realization of the experiments▪ Stable storage system: easy to store (stackable), fast control on

completeness (foam inserts)▪ Interactive executing of the experiments with help of inter-

TESS, a software to the PC supported experimentation andevaluation

▪ The use of the software minimizes preparation time and facil-itates individual learning-speeds

List of topics Inorganic ChemistryList of topics Inorganic Chemistry

1. Metals1. Metals- Oxidation of metals; Factors determining the reaction be-haviour of metals; Oxygen, causative agent of oxidation2. Air and other gases2. Air and other gases- The importance of air for combustion processes- Air, a mixture; Properties of oxygen- Reaction in pure oxygen; Quantitative investigation of ox-ides- Nitrogen, preparation and properties- Carbon dioxide, preparation and properties; Model of afire extinguisher- Construction and function of a Bunsen burner- The candle's flame; Rusting - “slow combustion”; Reduc-tion of copper oxide3. Water – components of water and water purification3. Water – components of water and water purification

- Water content of natural substances; Dissolved compon-ents in different waters- Solubility of gases in water; Solutions, colloids, suspen-sions- Solubility of salts in water - comparison with the solubil-ity of gases in water- Mode of operation of an aeration tank (sewage treatmentplant)- Water treatment in sewage treatment plants- Hardness of water; Test for water; Water, an oxide- Degradation of water by reducing agents; Synthesis ofwater4. Building material4. Building material- Production of cement; Processing of gypsum- Gypsum moulds5. Fertilizer5. Fertilizer- Mineral constituents of plants- Absorption of mineral substances by plants- Ammonia fertilizer; Burnt lime serving as a fertilizer6. Glass manufacture6. Glass manufacture- Soda-lime glass beads

Additionally required materialAdditionally required material

15301-8815301-88 TESS advanced Chemistry set Inorganic ChemistryTESS advanced Chemistry set Inorganic Chemistry

Properties of oxygen.

TESS advanced Inorganic Chemistry, consumables andTESS advanced Inorganic Chemistry, consumables andchemicals for 10 groupschemicals for 10 groups

13301-1013301-10

TESS advanced Inorganic Chemistry, necessary AccessoriesTESS advanced Inorganic Chemistry, necessary Accessoriesfor 1 groupfor 1 group

13433-8813433-88

2 Preparatory Course2 Preparatory Course2.3 Inorganic Chemistry


14

161619192424282837374141

General ChemistryGeneral Chemistry3.13.1 EquilibriaEquilibria3.23.2 Molar MassMolar Mass3.33.3 Acids and BasesAcids and Bases3.43.4 Solutions and MixturesSolutions and Mixtures3.53.5 Redox ReactionsRedox Reactions3.63.6 StoichiometryStoichiometry

3 General Chemistry3 General Chemistry


15

PrinciplePrinciple

Many metals, in particular transition elements, can form com-plexes with charged or neutral ligands. Complex formation reac-tions are equilibrium reactions. The stability of these complexes isdescribed by the complex formation constant.

TaskTask

Determine the number of ligands of the silver amine complex witha precipitation titration from a silver salt solution.

What you can learn aboutWhat you can learn about

▪ Complex formation▪ Chemical equilibrium▪ Equilibrium constant

Main articlesMain articles

Magnetic stirrer Mini / MST 47334-93 1

Silver nitrate, cryst. 15 g 30222-00 1

Retort stand, h = 750 mm 37694-00 1

Burette, lateral stopcock, Schellbach, 25 ml,graduations 0.05 ml 36506-01 1

Burette clamp, roller mount., 2 pl. 37720-00 1

Set of Precision Balance Sartorius CPA 623Sand measure software, 230 V 49224-88 1

Set of Precision Balance Sartorius CPA 623SSet of Precision Balance Sartorius CPA 623Sand measure software, 230 Vand measure software, 230 V


The balances of the Sartorius CPA series convince already at firstsight through an attractive, high-quality design - of the display upto the weighing pan. Onto the second look the "inner values" im-press and that amazing price/power ratio. The "mechanical heart"of these balances is the patented monolithic weighing systemwhich guarantees for confident and extremely precise weighing-results and beats in all models of the Sartorius CPA series. Thatensures extremely precise weighing-results to your lab at shortestmeasuring times. Premium balances is also at Sartorius in anycase: very best product quality with lasting reliability.

49224-8849224-88

P3031001P3031001 Complex formation equilibrium / complex formation constantComplex formation equilibrium / complex formation constant

Determination of the number of ligands boundin the complex.

3 General Chemistry3 General Chemistry3.1 Equilibria


16

PrinciplePrinciple

Carboxylic acids are potential electrolytes which exist in a weaklydissociated condition in aqueous solutions. The location of thedissociation equilibrium is quantitatively described by the Ka orpKa value which can be determined with potentiometric measure-ments.

TasksTasks

1. Measure the alteration of the pH value during a titration ofapproximately 0.1 molar aqueous solutions of formic acid,acetic acid, monochloroacetic acid, propionic acid, butyricacid and lactic acid with a 0.1 molar sodium hydroxide solu-tion at constant temperature using Cobra4 system.

2. From the neutralisation curves read the pKa values of theacids and compare them.


▪ True and potential electrolytes▪ Strong and weak acids▪ Law of mass action▪ Henderson-Hasselbalch equation▪ Dissociation constant and pKa value▪ Substituent effects▪ Potentiometry


Cobra4 Wireless Manager 12600-00 1

Cobra4 Wireless-Link 12601-00 2

Cobra4 Sensor-Unit Chemistry, pH and 2 xTemperature NiCr-Ni 12630-00 1

Cobra4 Sensor-Unit Drop Counter 12636-00 1

Software Cobra4 - multi-user licence 14550-61 1

Immersion probe NiCr-Ni, teflon, 300 °C 13615-05 1


Cobra4 Sensor-Unit Drop CounterCobra4 Sensor-Unit Drop Counter


The Cobra4 Drop Counter serves to count the number of drops thatfall from a burette and so, indirectly, to quantitativelydetermine the volume of a liquid that flows from the burette.

The Cobra4 Sensor-Unit Drop Counter can be connected to oneof the following devices to transfer the measured data: Cobra4Wireless-Link, Cobra4 Mobile-Link, Cobra4 USB-Link or Cobra4Junior-Link.

12636-0012636-00

P3030960P3030960Dissociation equilibrium (with Cobra4)Dissociation equilibrium (with Cobra4)

Neutralisation curve of formic acid.



17

P3030862P3030862

PrinciplePrinciple

The solubility of poorly soluble salts is expressed as the solubilityproduct, i.e. the product of the concentration of cations and an-ions in the solution which are in equilibrium with the solid salt.These concentrations can be determined via conductivity meas-urements.

Solubility product (with Cobra4)Solubility product (with Cobra4)

For more details refer to page 33.For more details refer to page 33.

P3030701P3030701

PrinciplePrinciple

At constant temperature and under constant pressure, a dis-solved substance distributes itself between two immiscible li-quids in a constant concentration ratio. This ratio is equal to thepartition coefficient (distribution coefficient) of the substanceexamined in the given two-phase system.

Distribution equilibriumDistribution equilibrium

For more details refer to www.phywe.comFor more details refer to www.phywe.com

P3031101P3031101

PrinciplePrinciple

The coloured indicator thymol blue is a weak acid that is partiallydissociated in aqueous solution, whereby non-ionized and ion-ized forms show absorption maximums at different wavelengthsin the visible range. Photometric measurements in the visiblespectral range can therefore be used to advantage to determinethe position of the Ka and pKa values of the indicator which char-acterize disscociation equilibrium.

Dissociation constantsDissociation constants




18

PrinciplePrinciple

All gases may be considered, to a first approximation, to obey theideal gas equation which relates the pressure p, volume V, tem-perature T and amount of substance n of a gas. The amount ofgas n is expressed as the number of moles and is equal to m / Mwhere m is the mass of gas present and M is the mass of onemole of the gas. The volume occupied by a known mass of gas isto be measured at a given temperature and pressure, so that theideal gas equation can be used to estimate the molar mass of thegas.

TaskTask

Determine the molar masses of the gases helium, nitrogen, carbondioxide, and methane.


▪ Molar mass and relative molar mass▪ Properties of gases▪ Ideal and ordinary gases▪ Equations of state


Rotary Vane pump, one stage, 115 V / 230 V 02740-95 1

Weather monitor, 6 lines LCD 87997-10 1

Sec.bottle500ml,2xGl18/8,1x25/12 34170-01 1

Oil mist filter, DN 16 KF 02752-16 1

Glass sphere,w. 2 stopcocks,100ml 36810-00 1


Rotary vane pump, one stage, 115 V/230 VRotary vane pump, one stage, 115 V/230 V


One-stage rotary vane pump suitable for the continuous operationin the rough and fine vacuum range.

BenefitsBenefits

The pump has a high water vapour tolerance and a compactdesign. Due to their low weight, small dimensions and the highpumping speed, this pump is ideal to use in schools and laborat-ories. It is low maintenance, compact and exceptionally quiet. Toprevent accidental damage the oil control glass is integrated intothe housing. The casing of the pump is easy to wipe clean. Since amale ground joint ST 19 is supplied with the pump, pump plateswith a ground socket ST19 can be put directly onto the pump..

02740-9502740-95

P3010401P3010401Determination of molar mass using the ideal gas lawDetermination of molar mass using the ideal gas law

Rearranging the ideal gas equation to determ-ine the molar mass.

3 General Chemistry3 General Chemistry3.2 Molar Mass


19

PrinciplePrinciple

The molar mass of a liquid is to be determined by evaporating aliquid at constant temperature and pressure, and measuring thevolume of vapour formed using a calibrated gas syringe.

TasksTasks

1. Determine the molar masses of diethyl ether and methanol.2. Discuss the results in terms of the real and ideal behaviour of

vapours.


▪ Ideal and ordinary gases▪ Equations of state for ideal gases▪ Gas volumetry▪ Determination of molar masses according to the vapour dens-

ity method (Victor Meyer)


Set gas laws with glass jacket, 230 V 43003-88 1


Power regulator 32288-93 1

Methanol 500 ml 30142-50 1

Diethyl ether 250 ml 30007-25 1


Set gas laws with glass jacket, 230 VSet gas laws with glass jacket, 230 V

Function and ApplicationsFunction and ApplicationsWith this set, experiments on the following topics can be carriedout:

▪ Gas law of Boyle-Mariotte▪ Gas law of Gay-Lussac▪ Gas law of Amonton (Charles)▪ Determination of molar masses according to the vapour dens-

ity method

BenefitsBenefitsThis set allows to execute the measurements in a didactical clearand easy understandable way:

▪ Clear setup; Easy to understand▪ Completely mercury-free▪ Quickly to execute; Short preparation time

43003-8843003-88

P3010501P3010501 Determination of the molecular mass of a liquidDetermination of the molecular mass of a liquid

Measurement results of the molecular mass formethanol and diethyl ether.



20

PrinciplePrinciple

Didactic setup to train and demonstrate the determination ofmolar masses by way of a measurement of the boiling pointelevation. The boiling point elevation of aqueous solutions ofdifferent substances is determined using. The ebullioscopic con-stant of water is calculated from the experimental results.

TasksTasks

1. Determine the boiling point elevation of aqueous solutions ofdifferent substances.

2. Calculate the ebullioscopic constant of water from the exper-imental results.


▪ Molar mass▪ Boiling point elevation▪ Ebullioscopy▪ Ebullioscopic constant


Temperature meter digital, 4-2 13617-93 1

Heating mantle for roundbottom flask, 250ml, 230 V, with safety switch 49542-93 1

Apparatus for elevation of boiling point 36820-00 1

Desiccator, Wertex, diam. 150 mm 34126-00 1


Temp. probe, immersion type, Pt100,stainless steel, -20...+300 °C 11759-01 1


Apparatus for elevation of boiling pointApparatus for elevation of boiling point

Function and ApplicationFunction and Application

Apparatus for determining molar mass, boiling point method.

Equipment and technical data:Equipment and technical data:

▪ 2 glass vessels of DURAN glass. The outer vessel has an inlet forintroduction of vapour from the solvent mixture.

A thin tube lies along the side of the inner vessel almost reachingthe bottom. This also allows the circulation of the escaping va-pour.

36820-0036820-00

P3021900P3021900Determination of molar masses via a measurement of the boilingDetermination of molar masses via a measurement of the boilingpoint elevation (ebullioscopy)point elevation (ebullioscopy)

Equation to demonstrate the ebullioscopic con-stants of solvents with known molecular weight.



21

PrinciplePrinciple

In order to train and demonstrate the determination of molarmasses by way of a measurement of the freezing-point depression,urea or hydroquinone are used as test substances. The cryoscopicconstant of water is determined from the freezing point depres-sion.

TasksTasks

1. Determine the freezing point depression of water dissolvingdifferent amounts of hydroquinone and urea.

2. Calculate the cryoscopic constant from the experimental res-ults.


▪ Cryoscopic constant▪ Freezing point depression▪ Molar mass



Magnetic stirrer MR Hei-Standard 35750-93 1

Desiccator, Wertex, diam. 150 mm 34126-00 1

Apparatus for freezing point depression 36821-00 1


Pellet press for calorimeter 04403-04 1


Apparatus for freezing point depressionApparatus for freezing point depression


Apparatus for determining molarmass, freezing point method.Theunit consists of an inner and an outer glass vessel of DURAN glass.The inner vessel has a flat bottom to accomodate magnetic stirrerbars and with lateral inlet for introduction of the substance to betested.

36821-0036821-00

P3022000P3022000 Determination of molar masses via a measurement of theDetermination of molar masses via a measurement of thefreezing point depression (cryoscopy)freezing point depression (cryoscopy)

Equation for the calculation of molar masses ofa dissolved substance based on the measure-ment of the freezing-point depression of thesolvent.



22

PrinciplePrinciple

A piece of metal is weighed and placed in the insert of the reactioncylinder, whereafter an acid is added to the cylinder through thethree-way valve until it is about half full. The metal is made to re-act with the acid by lowering the insert. The gas syringe connectedto the reaction cylinder is used to collect the hydrogen which isgenerated. The mass of the metal and the volume of the hydrogengenerated are used to calculate the desired molar mass. The reac-tion can also be used to determine the valency of the metal.

TaskTask

Determine the molar mass of zinc.


▪ Molar mass▪ Molar volume▪ Ideal gas laws


Cobra4 hand-held pressure and temperaturemeasuring instrument, Cobra4 Mobile-Link 12736-00 1

Frame for complete experiments 45500-00 1

Reaction cylinder with stopcock, GL25 35852-15 1

Holder for syringes 45523-00 1

Gas syringe, 100 ml, with 3-way cock 02617-00 1

Panel for complete experimental setups 45510-00 1

Clamping holder, 0-13 mm, fixed magnet 02151-07 1

Cobra4 hand-held pressure andCobra4 hand-held pressure andtemperature measuring instrument,temperature measuring instrument,Cobra4 Mobile-LinkCobra4 Mobile-Link


A combination of the Cobra4 Mobile-Link unit with the Cobra4Sensor-Unit Thermodynamics is ideal for the measurement ofpressure and temperatures simultaneously.

BenefitsBenefits

Cobra4 Mobile-Link is a modern, powerful hand-held measuringdevice, to which any Cobra4 sensor units can be connected via asecure snap-in connection.

12736-0012736-00

P1309400P1309400Determination of the molar masses of metalsDetermination of the molar masses of metals

General equation to identify metals using themethod of this experiment.



23

PrinciplePrinciple

pH values can be measured with the aid of electrochemical meas-urements and proton-sensitive electrodes (e.g. glass electrodes).By combining a glass electrode with a reference electrode in onehousing, a single-rod glass electrode, which is appropriate foracid-base titrations, is created. The titration curves allow an exactdetermination of the equivalence point in titrations of strong andweak acids and bases.

TasksTasks

1. Determine the titration curves of different neutralisation re-actions.

2. Determine the titration curve of an ampholyte (glycine).3. Determine the buffering capacity of various aqueous acetic

acid/sodium acetate mixtures at different total concentra-tions.


▪ Strong and weak electrolytes; Hydrolysis▪ Dissociation of water; Amphoteric electrolytes▪ Isoelectric point; Law of mass action; Indicators▪ Glass electrode; Activity coefficient; Buffering capacity▪ Henderson-Hasselbalch equation







Immers. probe NiCr-Ni, teflon, 300 °C 13615-05 1


Cobra4 Sensor-Unit Drop CounterCobra4 Sensor-Unit Drop Counter


The Cobra4 Drop Counter serves to count the number of drops thatfall from a burette and so, indirectly, to quantitativelydetermine the volume of a liquid that flows from the burette.

The Cobra4 Sensor-Unit Drop Counter can be connected to oneof the following devices to transfer the measured data: Cobra4Wireless-Link, Cobra4 Mobile-Link, Cobra4 USB-Link or Cobra4Junior-Link.

BenefitsBenefits

▪ Automatic performance of titration measurements▪ Each single drop reliably measured▪ Easy calculation of the volume in the software▪ Easy to mount

12636-0012636-00

P3061660P3061660 Titration curves and buffering capacity (with Cobra4)Titration curves and buffering capacity (with Cobra4)

Titration curve of acetic acid with sodium hy-droxide solution.

3 General Chemistry3 General Chemistry3.3 Acids and Bases


24

PrinciplePrinciple

When a strong acid is neutralised with a strong base in dilute solu-tion, the same amount of heat is always released. If the reactiontakes place under isobaric conditions, this heat is known as theenthalpy of neutralisation. The chemical reaction which generatesthis heat is the reaction of protons and hydroxyl ions to formundissociated water. It therefore correlates to the enthalpy offormation of water from these ions.

TasksTasks

1. Measure the temperature change during the neutralisationof a dilute potassium hydroxide solution with dilute hydro-chloric acid.

2. Calculate the enthalpy of neutralisation.


▪ Enthalpy of neutralisation▪ Calorimetry▪ Heat capacity


Set calorimetry, 230 V 43030-88 1

Cobra3 Data acquisition set for setcalorimetry 43030-30 1

Delivery pipette 04402-10 1

Potassium hydroxid for 1l 1mol solutionamp. 31425-00 1

Hydrochloric acid for 1mol solution amp. 30271-00 1

Rubber bulb, double 39287-00 1


Cobra4 Experiment - available 2013Cobra4 Experiment - available 2013

Set calorimetry, 230 VSet calorimetry, 230 V


With this setup a great number of measurements to heat capa-cities, reaction enthalpies, solution enthalpies, neutralisation en-thalpies, melting enthalpies and enthalpies of mixtures can becarried out.

43030-8843030-88

P3020811P3020811Determination of the enthalpy of neutralisation (with Cobra3)Determination of the enthalpy of neutralisation (with Cobra3)

Temperature-time curve of neutralisation anddetermining the heat capacity of the system.

Determination of the enthalpy of neutralisation (withDetermination of the enthalpy of neutralisation (withCobra4)Cobra4)

P3020860P3020860



25

PrinciplePrinciple

Some gases such as hydrogen chloride dissolve readily in water.For example, 1 litre of water at 20 °C can dissolve approximately443 litres of hydrogen chloride. For example, vacuum builds upquickly in a closed flask when the gas comes in contact with water,because the gas dissolves in the water and additional water isdrawn into the flask. This is the basis of how the chemical foun-tain works - an exciting way to demonstrate the solubility of gasesin water.In the variant depicted here, the hydrogen chloride is generated,fills the flask of the fountain and causes the fountain to fizz - allin a single apparatus.

TaskTask

Show the great solubility of hydrochloric acid in water using thechemical fountain.


▪ Solubility▪ Hydrochloric acid▪ Acids



Funnel for gas generator, 50 ml, GL18 35854-15 1

Apparatus carrier w. fix. magnet 45525-00 1


Quartz glass wool 10 g 31773-03 1

Glass sphere with 4 tubes 44551-00 1

Clamping holder, turnable, 18-25 mm 45521-00 1

Panel for complete experiment setupsPanel for complete experiment setups


Panel with regular punching to receive the hooks of the holder ho-rizontal or vertical positioning in the frame, one panel is necces-sary for each experiment.

Equipment and technical dataEquipment and technical data

▪ Material: sheet steel, powder painted with good mechanicaland chemical resistance

▪ Dimensions (LxHxW): 65x48.8x2.5 cm

45510-0045510-00

P1310100P1310100 Chemical fountainChemical fountain

Dissolution of hydrogen chloride in water. Ap-prox. 443 l of hydrogen chloride are soluble in 1l of water.



26

P3121260P3121260

PrinciplePrinciple

Phosphoric acid and sodium hydroxide are to be used to give anexample of a titration of a polyvalent acid with a strong base.


▪ Phosphoric acid▪ Sodium hydroxide▪ Polyvalent acid▪ pKa values▪ Proteolysis▪ pH value

Titration of a polyvalent acid with a strong base (with Cobra4)Titration of a polyvalent acid with a strong base (with Cobra4)


P3121360P3121360

PrinciplePrinciple

Acetic acid and sodium hydroxide are to be used to give an ex-ample of a titration of a weak organic acid with sodium hydrox-ide.


▪ Buffer▪ Neutralisation▪ pH-value▪ Henderson-Hasselbalch equation▪ pKa value

Titration of a weak organic acid with sodium hydroxide (with Cobra4)Titration of a weak organic acid with sodium hydroxide (with Cobra4)


P3121460P3121460

PrinciplePrinciple

The titration of ammonia solution with hydrochloric acid is usedhere as a typical example of a titration of a weak base with astrong acid.


▪ Buffer▪ Neutralisation▪ pH-value▪ Henderson-Hasselbalch equation▪ pKa value

Titration of a weak base (ammonia) with a strong acid (with Cobra4)Titration of a weak base (ammonia) with a strong acid (with Cobra4)




27

PrinciplePrinciple

A number of different mixtures of phenol and water are preparedand heated until complete miscibility is achieved. As the mixturescool, two-phase systems form at certain temperatures which arerecognisable by the appearance of turbidity. Plotting separationtemperatures against compositions of the mixtures gives theseparation curve.

TasksTasks

1. Plot the separation curve of the phenol / water binary systemand prepare a temperature / mass fraction diagram.

2. Determine the critical separation point.


▪ Binary system▪ Miscibility gap▪ Mixed phase▪ Coexisting phase▪ Raoult's law▪ Critical dissolution temperature


Immersion thermostat Alpha A, 230 V 08493-93 1

Bath for thermostat, Makrolon 08487-02 1

Rack for 20 test tubes, Makrolon 08487-03 1

External circulation set f. thermostat Alpha A 08493-02 1




P3030501P3030501 Solubility diagram of two partially miscible liquidsSolubility diagram of two partially miscible liquids

Solubility diagram of the phenol/water system.

3 General Chemistry3 General Chemistry3.4 Solutions and Mixtures


28

PrinciplePrinciple

A number of completely miscible two component mixtures are pre-pared to investigate the three component acetic acid / chloroform/ water system. These mixtures are titrated with the third com-ponent until a two phase system is formed which causes turbidity.The phase diagram for the three component system is plotted in atriangular diagram.

TasksTasks

1. Titrate nine different acetic acid / chloroform mixtures withwater until a two phase system is formed in each case.

2. Titrate six acetic acid / water mixtures with chloroform untilphase separation is observed.

3. Plot the results of the titrations, expressed as molar fractions,in a triangular diagram.


▪ Three component system▪ Miscibility gap▪ Phase diagram▪ Triangular diagram▪ Gibb's phase law




Rack for 20 test tubes, Makrolon 08487-03 1



Periodic system with colour picturesPeriodic system with colour pictures


Wall map in multicoloured offset printing on flexible Pretex-foilwith rods.

BenefitsBenefits

▪ The elements are shown with an application, the commercialform, radioactive elements with the radioactivity symbol andthe half-life.

▪ The photos supply informations about appearance and ag-gregate state, metal or nonmetal character, modifications,storage and reactivity of the elements.

▪ Important correlations of the periodic table can be recognizedimmediately, basic properties of the elements are memorized.


▪ Dimensions (L x H): 195 x 138 cm

47310-0247310-02

P3030601P3030601Miscibility gap in a ternary systemMiscibility gap in a ternary system

Triangular diagram of the system acetic acid/chloroform/water.



29

PrinciplePrinciple

Acid rain is caused by emissions from power plants, householdsand traffic. Gases such as sulfur dioxide, nitrogen dioxide and car-bon dioxide dissolve in rainwater, the products of which form theacids (acids containing sulfur, nitrous acid, nitric acid, carbonicacid). Acid rain reduces the pH of soils and waters. Environmentaldamage such as forest dieback is the result.

In this experiment acid rain will be produced artificially by addingthe gases SO2, NO2 and CO2 to water. The fall of the pH value is re-gistered.

TaskTask

Add the gases SO2, NO2 and CO2 to water and record the fall of thepH value.


▪ Acid rain▪ Anthropogenic air pollution▪ Damage to forests▪ Acidification of soil and water▪ Gaseous and aerosol emissions




Cobra4 Sensor-Unit pH, BNC connector 12631-00 1

pH-electrode, plastic body, gel, BNC 46265-15 1



Separatory funnel, 100 ml pear-sh. 36883-00 1

Cobra4 Wireless-LinkCobra4 Wireless-Link


Interface module for the radio-based transmission of sensormeasuring values in conjunction with the Cobra4 Wireless Man-ager.

BenefitsBenefits

▪ All Cobra4 Sensor-Units can be quickly connected using a se-cure and reliable plug-in / lockable connection.

▪ All Cobra4 measuring sensors are easy to plug in andautomatically detected.

▪ The radio network with the Cobra4 Wireless Manager is estab-lished automatically and is extremely stable, as it uses its ownradio protocol.

▪ Up to 99 Cobra4 Wireless-Links can be connected to one Co-bra4 Wireless Manager.

▪ No more cable mess, thanks to radio measuring.▪ With radio transmission, moving sensors offer completely new

experimentation options, e.g. the measurement of accelera-tion of a student on a bicycle etc.

12601-0012601-00

P4100760P4100760 The origin of acid rain (with Cobra4)The origin of acid rain (with Cobra4)

pH-time curve for SO2, NO2 and CO2.



30

PrinciplePrinciple

A concentration cell is constructed from two half-cells which areidentical, except that the concentration of the ionic species towhich the electrode is sensitive is different in the two sides ofthe cell. Such a cell may be used to measure the solubility productof a sparingly soluble salt. In one half-cell the concentration ofthese ions is known, in the other it is determined by the solubilityproduct of the salt under investigation. The ratio of the two con-centrations (more accurately, activities) determines the e.m.f. ofthe cell.

TaskTask

Use a concentration cell made from two Ag(s) l Ag+(aq) electrodes,to determine the solubility product of the three silver halides AgCl,AgBr and AgI.


▪ Concentration cells without transport; Electromotive force▪ Salt bridge; Liquid junction and diffusion potentials


Cobra4 Mobile-Link 12620-00 1




Silver foil, 150 x150 x 0.1 mm, 25 g 31839-04 1

Clay pins, d = 8 mm, l = 15 mm, 2 pcs. 32486-00 1

Set of Analytical Balance Sartorius CPA 224Sand measure software, 230 V 49221-88 1

P3061062P3061062Concentration cells without transport: Determination of theConcentration cells without transport: Determination of thesolubility products of silver halides (with Cobra4)solubility products of silver halides (with Cobra4)

Mean acitvity coefficients f± for AgNO3, KCl, KBr,KI at T = 25 °C.



31

PrinciplePrinciple

Osmosis describes the phenomenon that solvent molecules movethrough a partially permeable membrane into a region of highersolute concentration. Thus, the concentration of solute is equal-ized on both sides. The experimental set-up consists of sevenchambers that are filled with solutions of sugar with differentconcentrations. The liquid column in the capillaries is determinedand the dependence of the osmotic pressure on the concentrationcan easily be shown.

TasksTasks

1. Investigate the phenomenom of osmosis in a simple modelexperiment.

2. Determine the dependence of osmotic pressure on concen-tration of dissolved molecules.


▪ Osmosis▪ Osmotic pressure▪ Concentration


Osmosis and electrochemistry chamber 35821-00 1

Supplement chamber for osmosis / electrochemistry 35821-10 5

Filtration stand for 2 funnels 33401-88 1

Scale 350 mm 64840-00 7

D(+)-glucose 1-hydr. 250 g 30237-25 1


Related ExperimentRelated Experiment

Jacobus Henricus van ’t HoffJacobus Henricus van ’t Hoff1901, Nobel Prize in Chemistry1901, Nobel Prize in Chemistry

P1135700P1135700 Osmosis - dependence of the osmotic pressure on theOsmosis - dependence of the osmotic pressure on theconcentrationconcentration

Levels of different solutions during experiment.

Determination of diffusion potentialsDetermination of diffusion potentials

P3061101P3061101



32

PrinciplePrinciple

The solubility of poorly soluble salts is expressed as the solubilityproduct, i.e. the product of the concentration of cations and an-ions in the solution which are in equilibrium with the solid salt.These concentrations can be determined via conductivity meas-urements.

TasksTasks

1. Measure the conductivities of saturated aqueous solutions ofthe salts calcium fluoride and calcium carbonate at 25 °C.

2. With the aid of tabulated ionic conductivities, calculate thesolubility products of the salts from their conductivities.


▪ Solubility▪ Dissociation▪ Electrolytic conductance▪ Activity



Cobra4 Sensor-Unit Conductivity+,Conductivity/ Temperature (Pt1000) 12632-00 1

Conductivity temperature probe Pt1000 13701-01 1





Cobra4 Sensor-Unit Conductivity+,Cobra4 Sensor-Unit Conductivity+,Conductivity/ Temperature (Pt1000)Conductivity/ Temperature (Pt1000)


The Cobra4 Sensor Unit Conductivity / Temperature (Pt1000) isa microcontroller-based measuring recorder with a 5-pin diodesocket for connecting conductance measuring sensors with a cellconstant of K = 1.00/cm or Pt1000 thermocouples.

BenefitsBenefits

▪ Measure conductivity or temperature - multipurpose-sensor.▪ The Cobra4 sensor may be connected directly to the Cobra4

Wireless-Link, the Cobra4 Mobile-Link, the Cobra4 USB-Link orthe Cobra4 Junior-Link using a secure and reliable snap-inconnection.

12632-0012632-00

P3030862P3030862Solubility product (with Cobra4)Solubility product (with Cobra4)

Ionic conductivities at infinite dilution.



33

PrinciplePrinciple

Carboxylic acids are potential electrolytes which exist in a weaklydissociated condition in aqueous solutions. The location of thedissociation equilibrium is quantitatively described by the Ka orpKa value which can be determined with potentiometric measure-ments.

TasksTasks

1. Measure the alteration of the pH value during a titration ofapproximately 0.1 molar aqueous solutions of formic acid,acetic acid, monochloroacetic acid, propionic acid, butyricacid and lactic acid with a 0.1 molar sodium hydroxide solu-tion at constant temperature using Cobra4 system.

2. From the neutralisation curves read the pKa values of theacids and compare them.


▪ True and potential electrolytes; Strong and weak acids; Law ofmass action

▪ Henderson-Hasselbalch equation; Dissociation constant andpKa value; Substituent effects; Potentiometry








Cobra4 Wireless ManagerCobra4 Wireless Manager


USB device for radio-based communication with the Cobra4Wireless-Link.

BenefitsBenefits

▪ Simply connect the device to the computer's USB port.▪ Up to 99 measuring sensors can be connected to one computer▪ Automatic detection of all connected measuring sensors.

12600-0012600-00

P3030960P3030960 Dissociation equilibrium (with Cobra4)Dissociation equilibrium (with Cobra4)

Neutralisation curve of formic acid.



34

PrinciplePrinciple

The coloured indicator thymol blue is a weak acid that is partiallydissociated in aqueous solution, whereby non-ionized and ion-ized forms show absorption maximums at different wavelengthsin the visible range. Photometric measurements in the visiblespectral range can therefore be used to advantage to determinethe position of the Ka and pKa values of the indicator which char-acterize dissociation equilibrium.

TasksTasks

1. Experimentally determine the extinction (absorbance) of anaqueous solution of thymol blue (thymolsulphonephthalein)in dilute HCl, NaOH and a buffer of known pH value as a func-tion of wavelength between 400 and 700 nm at constantconcentration and constant temperature.

2. Calculate the dissociation constant (indicator constant) Kafrom the measurement results.


▪ True and potential electrolytes; Strong and weak acids▪ Law of mass action; Dissociation constants and pKa values▪ Henderson-Hasselbalch- Equation; UV-VIS spectrometry▪ Lambert-Beer's Law; Photometry


Spectrophotometer 190-1100 nm 35655-93 1

Cells for spectrophotometer, opt. glass, 2 pcs. 35664-02 1

Buffer solution, pH 9 1000 ml 30289-70 1

Ethyl alcohol, absolute 500 ml 30008-50 1

Thymol blue indicator 5 g 31896-02 1

Thermometer -10...+50 °C 38034-00 1


Spectrophotometer 190-1100 nmSpectrophotometer 190-1100 nm


Spectrophotometer 190-1100 nm

BenefitsBenefits

▪ The UV-VIS spectral photometer is characterised by its compactdesign and due to its wide range of possible uses.

▪ Operation is via a clearly set out overlay keyboard on thescreen dialogue.

▪ Current wavelengths and measured values can be displayed inlarge format.

▪ Alternatively, all measured values can also be presentedgraphically or in table format on the LCD screen with back-ground lighting.

▪ Strong light, high performance optics enable absorption andtransmission measurements to be taken in the wholewavelength range of 200 to 1100 nm with automatic switch-ing between the two light sources.

35655-9335655-93

P3031101P3031101Dissociation constantsDissociation constants



35

P3021001P3021001

PrinciplePrinciple

The boiling point of a solution is always higher than that of thepure solvent. The dependence of the temperature difference(elevated boiling point) on the concentration of the solute can bedetermined using a suitable apparatus.

Boiling point elevationBoiling point elevation


P3021101P3021101

PrinciplePrinciple

The freezing point of a solution is lower than that of the puresolvent. The depression of the freezing point can be determinedexperimentally using a suitable apparatus (cryoscopy). If the cryo-scopy constants of the solvent are known, the molecular mass ofthe substance dissolved can be determined.

Freezing point depressionFreezing point depression




36

PrinciplePrinciple

The experiments described here are highly suitable for demon-strating the different affinity of various metals in view of oxygen.The less noble a metal is the higher its affinity to oxygen and themore thermal energy is released during its oxidation. The technic-al importance of the thermite process for the welding of iron partsis that it is relatively easy to produce large amounts of liquid ironand, thereby, to fill wider weld grooves. This is why this processis mainly used for welding thick steel beams, rail tracks, and ma-chine parts.

TasksTasks

1. Reduction of copper oxide with iron.2. Reduction of iron oxide with aluminium (thermite process,

aluminothermics).


▪ Redox reaction; Thermite process▪ Metals; Welding of iron; Aluminothermics▪ Iron; Aluminium



Iron powder xtra pure 1000 g 30068-70 1

Magnet, d = 10 mm, l = 200 mm 06311-00 1

Teclu burner, DIN, natural gas 32171-05 1

Ignition sticks for thermite, 50 pcs. 31921-05 1


P3110600P3110600Redox reactions between metals and metal oxides (thermiteRedox reactions between metals and metal oxides (thermiteprocess)process)

Experimental setup.

3 General Chemistry3 General Chemistry3.5 Redox Reactions


37

PrinciplePrinciple

The reduction, as the reversal of the oxidation, can be achievedthermally or with the aid of a reducing agent.Some metal oxides can be decomposed into the metal and oxygenunder the influence of thermal energy. In the case of less noblemetals, a reducing agent is required for obtaining the elements.The redox processes during the preparation of lead demonstratethe relationship between oxidation and reduction.

By way of this experiment it can be shown that during the re-duction of an oxide the reducing agent itself is oxidised: hydrogento water, carbon to carbon dioxide. A reduction process is alwayscoupled with an oxidation process, which is why this type of reac-tion is referred to as a redox reaction.

TasksTasks

1. Reduction of lead(IV) oxide to lead(II) oxide by thermolysis.2. Reduction of lead(II) oxide by way of charcoal to obtain ele-

mentary lead.3. Reduction of iron oxide including the formation of hydrogen

based on pyrophoric iron.


▪ Reduction; Oxidation; Redox reaction▪ Lead; Iron; Thermolysis


Steel cylinder hydrogen, 2 l, full 41775-00 1

Gas bar 40466-00 1

Reducing valve for hydrogen 33484-00 1

Table stand for 2 l steel cylinders 41774-00 1

Combustion tube, 300 mm, quartz, ns 33948-01 1

Gas barGas bar


Gas bar to provide small quantities of gas ready to use, e.g. hy-drogen and oxygen when using the eudiometer. The required gasquantity can be removed with a syringe through the rubber cap.Two small gasometers, capacity app. 200 mml gas. Each max.filling pressure 30 bar. With tripod and stickers for labelling.

40466-0040466-00

P3100300P3100300 Reduction - reducing agents - redox processReduction - reducing agents - redox process

Reduction of ferric oxide with hydrogen.



38

PrinciplePrinciple

Lead oxide is reduced to lead; in the process the carbon is oxidisedto carbon dioxide. ln this experimental set-up and also in theblast furnace process, the reducing agent proper is not carbon, butrather the carbon monoxide generated due to the oxygen deficit.

TaskTask

Demonstrate the reduction of lead oxide.


▪ Lead▪ Carbon monoxide▪ Reduction▪ Oxidation▪ Redox reaction


Support base variable 02001-00 1

Lead-II oxide -litharge- 500 g 31121-50 1

Bunsen burner DIN, natural gas 32165-05 1

Activated carbon, granular 250 g 30011-25 1

Ring with boss head, i. d. = 10 cm 37701-01 1

Support rod, stainless steel, l = 600 mm, d =10 mm 02037-00 1

Safety gas tubing, DVGW, sold by metre 39281-10 1

P3100400P3100400Reduction of lead oxideReduction of lead oxide

The blast furnance with which iron can be ob-tained from iron oxide.



39

P3110400P3110400

PrinciplePrinciple

The contact process is currently used in the chemical industryto produce sulphuric acid in the high concentrations neededfor industrial processes. In this model experiment, platinum-palladium-aluminium-oxide beads are employed as a catalyst forthe reaction.

Sulphur trioxide - the sulphuric acid contact processSulphur trioxide - the sulphuric acid contact process


P3110500P3110500

PrinciplePrinciple

This is a model experiment to show the industrial blast furnaceprocess to produce iron from iron(III) oxide. During the experi-ment a furnace gas flame that is approximately 10 to 20 cm highcan be ignited at the stack outlet. Cavities form in the burningcarbon layer. These cavities collapse over time. Apart from ashand carbon residues, metallic lumps can also be found in theframe after the end of the experiment. Samples of these lumpslead to the formation of hydrogen when they are treated withhydrochloric acid.

Preparation of iron from oxidic ores (blast furnace process)Preparation of iron from oxidic ores (blast furnace process)


P3121060P3121060

PrinicplePrinicple

Potassium permanganate solutions which are used as oxidizingmeasuring solutions in redox titrations can in most cases be re-placed by Ce(IV) solutions. These offer the advantages that theydo not change on storage and that the course of the redox ti-tration can be very conveniently followed by measuring the elec-trochemical potential. The equivalent point can then be foundby determination of the inflection point of the potential curvewhich results from plotting the measured values.

Volumetric redox titration: Cerimetry (with Cobra4)Volumetric redox titration: Cerimetry (with Cobra4)




40

PrinciplePrinciple

A quiescent eudiometer is inserted into the glass jacket and theglass jacket is filled with cold water. Gas mixtures composed of hy-drocarbons and oxygen are injected into the eudiometer and burnthere continuously at the constant sparking of the ignition sparkgap. The water formed by the reaction condenses on the cool wallsof the eudiometer. For this reason, the volume between the mov-ing plunger and the fixed plunger with the ignition system aftercombustion is smaller than the volume of the gas mixture origin-ally injected. In a second part of the experiment, the eudiometerin the glass jacket is heated up to over 100°C. The water formedduring combustion can no longer condense on the hot eudiometerwalls.

In most cases, even after conversion to standard conditions, thevolume recorded then is greater than the volume of the gas thatwas injected. The easiest way to convert the volumes to standardconditions is with a nomogram. The measurement data obtainedin this way can be used to derive the empirical formulas of gaseoushydrocarbons experimentally.


High voltage supply unit, 0-10 kV 13670-93 1

Slow eudiometer 02612-00 1


Glass jacket 02615-00 1

Heating apparatus for glass jacket system 32246-93 1

Steel cylinder oxygen, 2 l, filled 41778-00 1


Slow eudiometerSlow eudiometer


Eudiometer, silent for the determination of volume ratios for con-tinuous combustion of gas mixtures.

BenefitsBenefits

▪ Glass cylinder with scale, as well as fixed and movable pistons▪ Ignition over a duration of sparks from a high voltage device▪ The gasmixtures are simply injected into the eudiometer using

an injection syringe.▪ The ignition of the gas mixture then occurs easily and safely

with the aid of the ignition spark generator.

02612-0002612-00

P3110900P3110900The empirical formula of methane, ethane and propaneThe empirical formula of methane, ethane and propane

Reaction equation of the combustion of hydro-carbons.

3 General Chemistry3 General Chemistry3.6 Stoichiometry


41

PrinciplePrinciple

In 1811, Avogadro stated his hypothesis that under the same con-ditions of pressure and temperature, equal volumes of all gasescontain equal numbers of components (molecules, atoms). He de-rived this from the uniformity of the behaviour of (ideal) gases onincreases in temperature and pressure (see the Gas Laws) and theLaw of Volumes. When Avogadro's supposition is correct, then 6parts by volume of CO and 3 parts by volume of 02 must form 6parts by volume of C02 when pressure and temperature are thesame before and after the reaction. Similarly, at a temperature alittle above 100°C, a gas mixture containing 6 parts by volume ofH2 and 3 parts by volume of 02 must give 6 parts by volume ofsteam, and a mixture containing 5 parts by volume of H2 and 5parts by volume of Cl2 must give 1 0 parts by volume of HCI. Inthe following experiments we will carry out the reactions namedabove to test the correctness of the hypothesis.

TasksTasks

Perform the following reactions to verify Avogadro's law:

1. Preparation of carbon monoxide and chlorine2. The carbon monoxide/oxygen reaction3. The hydrogen/oxygen reaction at above 100°C4. The hydrogen/chlorine reaction at above 100°C


▪ Avogadro; Gas laws; Carbon monoxide▪ Hydrogen; Chlorine; Oxygen


Plunger eudiometer 02611-00 1






Plunger eudiometerPlunger eudiometer


The plunger eudiometer consists of aglass cylinder with movableplunger and is used to determine the ratio of volumes in explosivegas reactions.

BenefitsBenefits

▪ Two 4-mmsockets connect the ignition spark generator.▪ This device can be used to cause gas mixtures to react at room

temperature, which lead to gaseous reaction products or inwhich residual quantities of the reaction gases remain in thecylinder (e.g. mixtures of air and hydrogen, of carbon monox-ide and oxygen).

▪ The gasmixtures are simply injected into the eudiometer usingan injection syringe.

▪ The ignition of the gas mixture then occurs easily and safelywith the aid of the ignition spark generator.

▪ If the plunger eudiometer is assembled in the glass jacket, theratio of volumes of gas reactions can also be investigated attemperatures other that room temperature, such as the re-action of a stochiometric mixture of hydrogen and oxygen atabove 100°C.

02611-0002611-00

P3111000P3111000 Avogadro's lawAvogadro's law

Schematical set-up of the experiment.



42

PrinciplePrinciple

The Briggs-Rauscher reaction is a so-called homogeneous oscillat-ing reaction, i.e. the reaction rate of the complete process is sub-ject to periodic fluctuations. In general, oscillating reactions canalways occur when the following conditions are fulfilled: The re-action must run highly exergonic (ΔG << 0). At least one of thereaction steps must contain a positive or negative back-coupling.Such back-coupling processes occur when the result of the indi-vidual partial steps of the reaction, such as changes in temperat-ure or concentration, act back on the rate constants of the indi-vidual partial steps of the reaction. In this way, the whole reactionbecomes non-linear.

TaskTask

Observer the fluctuations of the Briggs-Rauscher reaction by meas-uring the potential over a definite time period.


▪ Oscillating reactions; Exergonic process▪ Potential, Briggs-Rauscher reaction








Cobra4 Wireless ManagerCobra4 Wireless Manager


USB device for radio-based communication with the Cobra4Wireless-Link.

BenefitsBenefits

▪ Simply connect the device to the computer's USB port.▪ Up to 99 measuring sensors can be connected to one computer▪ Automatic detection of all connected measuring sensors.


▪ Power consumption: < 100 mA▪ Connection voltage (via USB): 5 V▪ Radio output power: 1 mW▪ Max. data rate (burst):125,000 values/s▪ Range with no obstacles: 20 m▪ max. number of Cobra4 Wireless-Links in the network: 99▪ Dimensions (LxBxH): 75 x 25 x 10 mm; Weight: 20 g

12600-0012600-00

P3121660P3121660Briggs-Rauscher Reaction (with Cobra4)Briggs-Rauscher Reaction (with Cobra4)

Graph of measured potential against time.



43

PrinciplePrinciple

A piece of metal is weighed and placed in the insert of the reactioncylinder, whereafter an acid is added to the cylinder through thethree-way valve until it is about half full. The metal is made to re-act with the acid by lowering the insert. The gas syringe connectedto the reaction cylinder is used to collect the hydrogen which isgenerated. The mass of the metal and the volume of the hydrogengenerated are used to calculate the desired molar mass. The reac-tion can also be used to determine the valency of the metal.

TaskTask

Determine the molar mass of zinc.


▪ Molar mass▪ Molar volume▪ Ideal gas laws




Reaction cylinder with stopcock, GL25 35852-15 1

Holder for syringes 45523-00 1



Clamping holder, 0-13 mm, fixed magnet 02151-07 1

Cobra4 hand-held pressure andCobra4 hand-held pressure andtemperature measuring instrument,temperature measuring instrument,Cobra4 Mobile-LinkCobra4 Mobile-Link


A combination of the Cobra4 Mobile-Link unit with the Cobra4Sensor-Unit Thermodynamics is ideal for the measurement ofpressure and temperatures simultaneously.

BenefitsBenefits

Cobra4 Mobile-Link is a modern, powerful hand-held measuringdevice, to which any Cobra4 sensor units can be connected via asecure snap-in connection.

12736-0012736-00

P1309400P1309400 Determination of the molar masses of metalsDetermination of the molar masses of metals

General equation to identify metals using themethod of this experiment.



44

464651515252

Analytical ChemistryAnalytical Chemistry4.14.1 TitrationTitration4.24.2 ElectrogravimetryElectrogravimetry4.34.3 ChromatographyChromatography

4 Analytical Chemistry4 Analytical Chemistry


45

PrinciplePrinciple

The electric conductivity of aqueous electrolyte solutions is de-termined by the type and number of charge carriers at constanttemperature. Characteristic changes in conductivity are connectedwith changes in the ionic composition of reacting systems. Thesecan be used in the conductiometric titration as end point indicat-ors.

TasksTasks

Using the Cobra4 system, measure the change in conductivity inthe titrations of the following:

1. approximately 0.1 molar barium hydroxide solution with 0.1molar sulphuric acid.

2. approximately 0.1 molar hydrochloric acid with 0.1 molar so-dium hydroxide solution.

3. approximately 0.1 molar acetic acid with 0.1 molar sodiumhydroxide solution.

Other samples can alternatively be set in advance for conduc-tiometric determination of their concentration contents.


▪ Electrolyte; Electrical conductance; Specific conductance▪ Ion mobility; Ion conductivity; Conductometry; Volumetry







Conductivity temperature probe Pt1000Conductivity temperature probe Pt1000


Conductivity temperature probe Pt1000.


▪ Cell constant k = 1.0 / cm▪ Minimum immersion depth: 10 mm

13701-0113701-01

P3060760P3060760 Conductivity titration (with Cobra4)Conductivity titration (with Cobra4)

Titration diagram for the neutralisation of HCIsolution with NaOH solution.

4 Analytical Chemistry4 Analytical Chemistry4.1 Titration


46

PrinciplePrinciple

The cell voltage and the Galvani voltage of the electrodes of a gal-vanic cell are dependent upon the concentration of the ions in-volved in the potential forming process. Thus, conclusions can bemade about the concentration of the ions to be investigated fromthe measured cell voltage at a constant potential of a suitable ref-erence electrode (potentiometric titration).

TasksTasks

Using the Cobra4-System, measure the change in the cell voltagein the titration of

a) diluted phosphoric acid with 0.1 molar sodium hydroxide solu-tion.

b) a sample of a carbonated beverage (Cola) containing phosphoricacid (E338) with 0.1 molar sodium hydroxide solution and calcu-late the beverage's phosphoric acid content from the consumptionof the standard solution.


▪ Galvanic cell; Types of electrodes; Galvani voltage▪ Cell voltage; Nernst equation; Potentiometry; Volumetry







Immers. probe NiCr-Ni, teflon, 300 °C 13615-05 1


P3061760P3061760Potentiometric pH titration (phosphoric acid in soft drinks) (withPotentiometric pH titration (phosphoric acid in soft drinks) (withCobra4)Cobra4)

Titration diagram of the neutralisation of abeverage containing phosphoric acid (V = 50 ml)with a 0.1 molar sodium hydroxide solution.



47

PrinciplePrinciple

Potassium permanganate solutions which are used as oxidizingmeasuring solutions in redox titrations can in most cases be re-placed by Ce(IV) solutions. These offer the advantages that they donot change on storage and that the course of the redox titrationcan be very conveniently followed by measuring the electrochem-ical potential. The equivalent point can then be found by determ-ination of the inflection point of the potential curve which resultsfrom plotting the measured values.

TaskTask

Titrate Iron(II) sulphate solution with Ce(IV) sulphate solution.


▪ Redox titration; Iron(II) sulphate▪ Ce(IV) sulphate; Titration▪ Cerimetry









Software Cobra4 - multi-user licenceSoftware Cobra4 - multi-user licence


The "measure Cobra4" measuring software leaves nothing to bedesired.

As soon as a Cobra4 sensor is connected to a PC, irrespective ofwhether by Cobra4 Wireless or Cobra4 USB Link, the "measureCo-bra4" software opens completely automatically and shows theconnected sensors, the required measuring windows and the cur-rent measuring data.

14550-6114550-61

P3121060P3121060 Volumetric redox titration: Cerimetry (with Cobra4)Volumetric redox titration: Cerimetry (with Cobra4)

Measurement curve for the titration of 10 ml ofan 0.1 molar Fe(II) sulphate solution with 10 mlof an 0.1 molar Ce(IV) sulphate solution withthe equivalent point entered.



48

PrinciplePrinciple

Precipitation reactions which occur stoichiometrically and rapidly,and whose equilibrium lies on the side of the poorly solubleproducts can also be used titrimetrically. Consequently, a solutionwhich contains both chloride and iodide ions can be titratedwith a silver nitrate solution. The course of the titration is mon-itored potentiometrically and the equivalence points are determ-ined from the inflection points of the potential curve.

TasksTasks

1. Titrate a solution which contains 10 ml each of 0.1 molar po-tassium chloride and potassium iodide solutions with a 0.1molar silver nitrate soltution.

2. Plot the potential of a silver electode measured against a sil-ver / silver chloride reference electrode as a function of theadded volumes of standard solution.

3. Determine the equivalence points from the inflection pointsof the potential curve.


▪ Electrode potential; Cell voltage▪ Electrodes of the 1st and 2nd type▪ Nernst equation; Argentometry; Solubility product







Cobra4 Sensor-Unit Chemistry, pH and 2 xCobra4 Sensor-Unit Chemistry, pH and 2 xTemperature NiCr-NiTemperature NiCr-Ni


The Cobra4 Sensor-Unit pH and 2 x temperature NiCr-Ni is a meas-uring recorder for pH, potential and temperature measurements,which is controlled by micro-controller.

BenefitsBenefits

▪ It can be fitted with two NiCr-Ni thermoelements (Type K) anda pH probe or redox measuring chain▪ Measure up to two temperatures and one pH or potential

value simultaneously.▪ Discover new experimental possibilities especially in ther-

modynamics

▪ Values of the calibration are saved in the sensor - no need fornew calibration after changing the basic unit.

12630-0012630-00

P3061460P3061460Precipitation titration (with Cobra4)Precipitation titration (with Cobra4)

Course of the potential during the precipitationtitration.



49

PrinciplePrinciple

pH values can be measured with the aid of electrochemical meas-urements and proton-sensitive electrodes (e.g. glass electrodes).

By combining a glass electrode with a reference electrode in onehousing, a single-rod glass electrode, which is appropriate foracid-base titrations, is created.

The titration curves allow an exact determination of the equival-ence point in titrations of strong and weak acids and bases.

TasksTasks

1. Determine the titration curves of different neutralisation re-actions.

2. Determine the titration curve of an ampholyte (glycine).3. Determine the buffering capacity of various aqueous acetic

acid/sodium acetate mixtures at different total concentra-tions.


▪ Strong and weak electrolytes▪ Hydrolysis▪ Dissociation of water▪ Amphoteric electrolytes▪ Isoelectric point▪ Law of mass action▪ Indicators▪ Glass electrode▪ Activity coefficient▪ Buffering capacity▪ Henderson-Hasselbalch equation









Related ExperimentsRelated Experiments

P3061660P3061660 Titration curves and buffering capacity (with Cobra4)Titration curves and buffering capacity (with Cobra4)

Titration curve of acetic acid with sodium hy-droxide solution.

Titration of a polyvalent acid with a strong base (withTitration of a polyvalent acid with a strong base (withCobra4)Cobra4)

P3121260P3121260

Titration of a weak organic acid with sodium hydroxideTitration of a weak organic acid with sodium hydroxide(with Cobra4)(with Cobra4)

P3121360P3121360

Titration of a weak base (ammonia) with a strong acidTitration of a weak base (ammonia) with a strong acid(with Cobra4)(with Cobra4)

P3121460P3121460



50

PrinciplePrinciple

Electrogravimetry is an important analytical method for thequantitative determination or separation of species in solution.The technique involves the quantitative electrolytic deposition ofan element, usually a metal, on a suitable electrode in weighableform.

TaskTask

Perform an accurate electrogravimetric determination of theamount of copper in a given sample solution.


▪ Quantitative analysis▪ Gravimetry▪ Electrolysis▪ Overpotential▪ Electrode polarisation


Pt electrodes, electrogravimetry 45210-00 1

Power supply, universal 13500-93 1


Electronic temperature controller EKT Hei-Con 35750-01 1

Digital multimeter 2010 07128-00 2



Power supply, universalPower supply, universal


Versatile heavy duty power supply which can also be used as a con-stant current supply in schools, laboratories or workshops.


▪ Direct current source: Stabilised, regulated output directvoltage, continuously adjustable from 0...18 V

▪ Adjustable current limit between 0...5 A▪ LED display for constant current operation▪ Permantely short-circuit proof & protected against exterior

voltages▪ Alternative voltage output:▪ Multitap transformer 2...15V, outputs galvanically separated

from main grid▪ Full load capacity (5 A), even if direct current is supplied sim-

ultaneously

13500-9313500-93

P3062201P3062201Electrogravimetric determination of copperElectrogravimetric determination of copper

Electric circuit for electrolysis.

4 Analytical Chemistry4 Analytical Chemistry4.2 Electrogravimetry


51

PrinciplePrinciple

Chromatographic separation processes are very important for ana-lytical chemistry. Their relatively simple technique and thepossibility to separate even the smallest portions of mixtures ex-plain the rapid development of these processes. There are numer-ous variations of this method.

As a result, the optimum chromatographic separation methodcan be found for nearly every separation task. The method thatis described here can be used to demonstrate the fundamentalprinciples and possibilities of this method with relatively simplemeans.

TaskTask

Separate a dye mixture by thin-layer chromatography.


▪ Thin-layer chromatography▪ Separation procedure▪ Adsorbent material▪ Stationary phase▪ Mobile phase▪ Capillary action


Separation chamber, 180x120x50 mm 35010-06 1

TLC-foil, silica gel F254, 25 off 31503-04 1


Methyl red 25 g 31574-04 1

Capillary holder 35010-07 1

Micro-capillaries, 2 / 1000 ml, 100 35010-08 1

Fuchsine powder 25 g 31320-04 1

Separation chamber, 180x120x50 mmSeparation chamber, 180x120x50 mm


Development vessel for thin-layer chromatography.


Dimensions: 120 mm×50 mm×180 mm

35010-0635010-06

P3120400P3120400 Chromatographic separation processes: thin layerChromatographic separation processes: thin layerchromatographychromatography

Part of the experimental setup

4 Analytical Chemistry4 Analytical Chemistry4.3 Chromatography


52

PrinciplePrinciple

Chromatographic procedures allow a separation of substance mix-tures with the aid of a stationary separation phase and a mobilephase.

In gas chromatography the mobile phase is a gas. The mobilephase, to which the mixture to be separated is added, transportsthe substance mixture through the separation column at a con-stant flow rate. Interactions occur between the mobile phase andthe stationary phase.

The establishment of equilibria between the stationary phase andthe different substances (distribution equilibria, adsorption-de-sorption equilibria) results in different migration rates of the in-dividual components.

At the end of the column there is a detector in the form ofa thermal conductivity cell, which can detect the different sub-stances on the basis of their differing thermal conductivities. Thedetector signal is recorded as a funtion of time.

The different thermal conductivities of the carrier gas and thesubstance cause temperature alterations in the electrically heatedtemperature sensor, which is located in a Wheatstone bridge cir-cuit. The resulting electrical signal is recorded by a plotter as afunction of time (chromatogram).

TasksTasks

1. Determine the retention times of different gases and performa chromatographic material separation of a mixture of bu-tane gases.

2. Separate and identify the components of a two-componentmixture consisting of ethanol and ethyl acetate chromato-graphically.


▪ Chromatography; Chromatogram; Multiplicative distribution▪ Nernst's law of distribution (number of theoretical trays)▪ Thermal conductivity detector







Control unit gas chromatograph 36670-99 1

Steel cylinder helium, 2 l, filled 41776-00 1

Archer J.P. Martin (left)Archer J.P. Martin (left)

Richard Laurence Millington Synge (right)Richard Laurence Millington Synge (right)

1953, Nobel Prize in Chemistry1953, Nobel Prize in Chemistry

P3031760P3031760Chromatographic separation processes: Gas chromatographyChromatographic separation processes: Gas chromatography(with Cobra4)(with Cobra4)

Gas chromatographic separation of a mixture ofbutane gases.



53

PrinciplePrinciple

In this investigation, a uniformly green raw extract of fresh leavesis first separated into different fractions by means ofcolumn chromatography. To do so, the extract is added to acolumn filled with starch and drawn through the column underslightly reduced pressure (to increase the flow rate of the mobilephase) with ligroin as the eluent. A separation occurs in a clearlyrecognisable, broad, yellow area and in a narrow, green band.This means that the xanthophylls (yellow) are separated from thechlorophylls (green). If the vacuum is reduced during the separa-tion, the separation is much better, but then separation also takesconsiderably longer. Each of the separation fractions can be col-lected individually and characterised by recording their absorptionspectra, if necessary, or examined for fluorescence by radiationwith UV light.

TaskTask

Investigate different leaf pigments using column chromatography


▪ Chlorophyll; Column chromatography▪ Leaf pigments; Xanthophyll



Secure bottle, 500 ml, 2 x Gl 18/8, 1 x 25/12 34170-01 1


Column for ion-exchange chromatography 35025-01 1

Vacuum adaptor, straight, GL25/12 35806-15 1

Spring manometer, 0...-1000 mbar 34170-02 1

P3120300P3120300 Column chromatography - separation of leaf pigmentsColumn chromatography - separation of leaf pigments

Leaf with green pigments.



54

565659596565

SpectroscopySpectroscopy5.15.1 X-ray Fluorescence AnalysisX-ray Fluorescence Analysis5.25.2 Nuclear Magnetic ResonanceNuclear Magnetic Resonance5.35.3 Photometry and PhotochemistryPhotometry and Photochemistry

5 Spectroscopy5 Spectroscopy


55

PrinciplePrinciple

Various powder samples are subjected to polychromatic X-rays. Theenergy of the resulting fluorescence radiation is analysed with theaid of a semiconductor detector and a multichannel analyser. Theenergy of the corresponding characteristic X-ray fluorescence linesis determined. The elements of the samples are identified by com-paring the line energies with the corresponding table values.

TasksTasks

1. Calibrate the semiconductor energy detector with the aid ofthe characteristic radiation of the tungsten X-ray tube.

2. Record the fluorescence spectra that are produced by thesamples.

3. Determine the energy values of the corresponding fluores-cence lines and compare the experimental energy valueswith the corresponding table values in order to identify thepowder components.


▪ Bremsstrahlung; Characteristic X-radiation▪ Energy levels; Fluorescent yield▪ Semiconductor energy detectors▪ Multichannel analysers


XR 4.0 expert unit 09057-99 1

XR 4.0 X-ray energy detector (XRED) 09058-30 1

XR 4.0 X-ray goniometer 09057-10 1

XR 4.0 X-ray plug-in unit W tube 09057-80 1

Multi channel analyser 13727-99 1

XR 4.0 X-ray Chemical set for edge absorption 09056-04 1

measure Software multi channel analyser 14452-61 1

Best fitting X-ray sets for this experiment:Best fitting X-ray sets for this experiment:

Multi channel analyserMulti channel analyser

Function and applicationsFunction and applications

The multi channel analyser is for analysing voltage pulses whichare proportional to energy and for determining pulse rates andintensities in conjunction with an X-ray detector, alpha detectoror gamma detector. The analogue pulses from the detector areshaped by the analyser, digitised and summed per channel ac-cording to pulse height. This results in a frequency distribution ofdetected pulses dependent on the energy of the radiation.

13727-9913727-99

P2544701P2544701 Qualitative X-ray fluorescence analysis of powder samplesQualitative X-ray fluorescence analysis of powder samples

Total representation of the Kα and Kβ fluores-

cence lines of the elements with an atomicnumber of 30 < Z < 38.

XRE 4.0 X-ray expert setXRE 4.0 X-ray expert set

09110-8809110-88

XRM 4.0 X-ray material analysis upgrade setXRM 4.0 X-ray material analysis upgrade set

09160-8809160-88

5 Spectroscopy5 Spectroscopy5.1 X-ray Fluorescence Analysis


56

PrinciplePrinciple

Various alloyed materials are subjected to polychromatic X-rays.The energy of the resulting fluorescence radiation is analysed withthe aid of a semiconductor detector and a multichannel analyser.The energy of the corresponding characteristic X-ray fluorescencelines is determined. In order to determine the concentration ofthe alloy constituents, the intensity of their respective fluores-cence signals is compared to that of the pure elements.

TasksTasks

1. Calibration of the semiconductor energy detector with theaid of the characteristic radiation of the tungsten X-ray tube.

2. Recording of the fluorescence spectra that are produced bythe alloyed samples.

3. Recording of the fluorescence spectra that are produced bythe pure metals.

4. Determination of the energy values of the correspondingfluorescence lines.

5. Calculation of the concentration levels of the alloy constitu-ents.


▪ Bremsstrahlung; Characteristic X-radiation▪ Energy levels; Fluorescent yield; Auger effect▪ Coherent and incoherent photon scattering▪ Absorption of X-rays; Edge absorption▪ Matrix effects; Semiconductor energy detectors▪ Multi channel analysers



XR 4.0 X-ray energy detector (XRED) 09058-30 1



Multi channel analyser 13727-99 1

XR 4.0 X-ray specimen set metals forfluorescence, set of 4 09058-34 1

XR 4.0 X-ray specimen set metals for X-rayfluorescence, set of 7 09058-31 1


XR 4.0 X-ray energy detector (XRED)XR 4.0 X-ray energy detector (XRED)


With the new X-ray energy detector you can directly determine theenergies of single x-ray quanta.

09058-3009058-30

P2545001P2545001Quantitative X-ray fluorescence analysis of alloyed materialsQuantitative X-ray fluorescence analysis of alloyed materials

Fluorescence spectrum of constantan, Kα-lines.


09110-8809110-88

XRM 4.0 X-ray material analysis upgrade setXRM 4.0 X-ray material analysis upgrade set

09160-8809160-88



57

P2545101P2545101

PrinciplePrinciple

Various solutions, with known element concentrations, are sub-jected to polychromatic X-rays. The energy and intensity of theresulting fluorescence radiation of the dissolved elements areanalysed with the aid of a semiconductor detector and a mul-tichannel analyser. In order to determine the unknown elementconcentrations in the solutions, calibration is performed. For thispurpose, the known element concentrations of the calibrationsolution are plotted against the corresponding fluorescence in-tensities of the dissolved elements.

Quantitative X-ray fluorescence analysis of solutionsQuantitative X-ray fluorescence analysis of solutions


P2544501P2544501

PrinciplePrinciple

Various metal samples are subjected to polychromatic X-rays. Theenergy of the resulting fluorescence radiation is analysed withthe aid of a semiconductor detector and a multi channel ana-lyser. The energy of the corresponding characteristic X-ray linesis determined, and the resulting Moseley diagram is used to de-termine the Rydberg frequency and the screening constants.

Qualitative X-ray fluorescence spectroscopy of metals - Moseley's lawQualitative X-ray fluorescence spectroscopy of metals - Moseley's law


P2544601P2544601

PrinciplePrinciple

The composition of various alloys is analysed with the aid of poly-chromatic X-rays. The energy of the characteristic fluorescencelines of the alloy constituents is analysed with the aid of a semi-conductor detector and a multichannel analyser. The alloy con-stituents are identified by comparing the line energies with thecorresponding table values.

Qualitative X-ray fluorescence analysis of alloyed materialsQualitative X-ray fluorescence analysis of alloyed materials




58

Compact MRTCompact MRT


The system gives you the unique opportunity of offering training ata real magnetic resonance tomograph (MRT), which is used in al-most all fields of science and medicine, directly on site. The train-ing software and the experiment instructions cover all key as-pects of the magnetic resonance technology, ranging from the ba-sic principles of nuclear magnetic resonance (NMR) to the com-plex high-resolution MR imaging (MRI). Thus, students can performsome basic experiments of the MR technology as well as gener-ate, export and analyze numerous high-resolution images in allrelevant contrasts. The special option to influence experiments onruntime and to directly visualize the results gives users an un-precedented learning experience. Thereby image artifacts found inclinical MRT can be examined directly in a simple process. The sys-tem consists of a "control unit" and a "magnet unit", which differfrom other magnetic resonance tomographs only in the size andthe fact that they are portable.

BenefitsBenefits

▪ Easy to connect and immediately operative (USB 2.0)▪ New and numerous education experience

▪ training with clinically relevant measuring procedures▪ high resolution MR imaging (2D, 3D)▪ live visualization of data▪ realtime control of experimental parameters

▪ Practice-oriented training for all fields of science and medi-cine▪ T1/T2 measurements▪ all MR parameters accessible▪ measure a multitude of samples with a diameter up to

one centimeter▪ software perfectly fits the study purposes▪ suitable for a wide range of experiments

▪ Literature tailored precisely to the experiments (5 TESS expertexperimental units: Basic principles in Nuclear Magnetic Res-onance (NMR), Relaxation times in Nuclear Magnetic Reson-ance, Spatial encoding in Nuclear Magnetic Resonance, Mag-netic Resonance Imaging (MRI) I, Magnetic Resonance Imaging(MRI) II)

▪ Possibility to select courses (Basic course, Basic principles,Relaxation, 1D spatial encoding, Imaging I, Imaging II)


The system includes the following components:

▪ Control unit:▪ Gradient amplifier and transmitter and receiver unit▪ PC connection USB-B▪ Connection of the imaging unit (gradient) RJ45▪ Connection of the receiver/transmitter unit BNC

▪ Power supply 12 V DC, 2 A▪ Power supply unit (external) 100-240 VAC, 50/60 Hz, 2 A▪ Dimensions (cm) 27 x 9.5 x 14▪ Weight 2.3 kg

▪ Magnet unit:▪ High-end gradient system for 2D and 3D images▪ System frequency 22 MHz▪ Field strength 500 mT▪ Field homogenity < 100 ppm▪ Sample diameter max. 10 mm▪ Connection of the imaging unit (gradient) RJ45▪ Connection of the receiver/transmitter unit BNC▪ Dimensions (length x width x height, cm) 27 x 25 x 14▪ Weight 17.5 kg

▪ Training software:▪ Languages German/English (other languages on re-

quest)▪ Product license measure MRT▪ Data formats DICOM, JPEG, CSV, TXT▪ Media types DVD

▪ Sample set▪ 5 different samples (water and oil samples each of with 5

and 10 mm diameter, sample with a particular structure)▪ 1 empty sample tube (10 mm)

▪ Soundbox for a realistic MR-noise▪ Connecting cables (2 x RJ45, 1 x BNC, USB)▪ Sturdy carrying case and shielded flight box for safe transport▪ DVD incl. training software, comprehensive descriptions of the

5 TESS expert experimental units with detailed theoreticalbackground, structured implementation plan, exercises, ana-lyses and many figures clearly arranged, operating instruc-tions, software instructions

AccessoriesAccessories

▪ Required for the experiments: Computer (min. processor 1.6GHz) with Windows XP (32-Bit)/Vista (32-Bit)/7, USB 2.0 inter-face, min. 1 GB RAM, min. of 1 GB hard-disk space, 1024 x758 graphics card (min. 256 MB, compatible with DirectX 9.0),16-bit color resolution or better

▪ Required for MR-noise: active loudspeakers▪ Options for experiments: other sample sets or own samples

09500-9909500-99

Cross-sectional image of a branch.Cross-sectional image of a branch.

5 Spectroscopy5 Spectroscopy5.2 Nuclear Magnetic Resonance


59



60



61

PrinciplePrinciple

The basic principles concerning the phenomenon of nuclear mag-netic resonance (NMR) are demonstrated. Experiments are ex-ecuted with a MRT training device giving the opportunity to in-vestigate some small probes in the sample chamber. Device controlis done with the provided software. Investigations comprise thetuning of the system frequency to the Larmor frequency, the de-termination of the flip angle of the magnetisation vector, the ef-fects of the substance quantity, the influence of particular mag-netic field inhomogeneities, the measurement of a spin echo sig-nal and an averaging procedure to maximise the signal-to-noiseratio. The adjustment of all parameters in these experiments areinevitable to obtain an adequate MR image.

TasksTasks

1. Tuning of the system frequency to the Larmor frequency.2. Setting of the HF (High Frequency) pulse duration to determ-

ine the flip angle of the magnetisation vector.3. Effects of the substance quantity on the FID signal (Free In-

duction Decay) amplitude.4. Minimising magnetic field inhomogeneities via a superim-

posed magnetic field (shim).5. Retrieving a relaxated FID signal via a spin echo flipping nuc-

lear spins by 180°.6. Improving the signal-to-noise ratio (SNR) of the FID signal.

What cou can learn aboutWhat cou can learn about

▪ Nuclear spins; Atomic nuclei with a magnetic moment▪ Precession of nuclear spins; Magnetisation▪ Resonance condition; MR frequency; MR flip angle▪ FID signal (Free Induction Decay); Spin echo▪ Relaxation times (T1: longitudinal magnetisation, T2: trans-

verse magnetisation)▪ Signal-to-noise ratio


Compact MRT 09500-99 1

Felix Bloch (left) and Edward Mills Purcell (right)Felix Bloch (left) and Edward Mills Purcell (right)

1952, Nobel Prize in Physics1952, Nobel Prize in Physics

P5942100P5942100 Fundamental principles of Nuclear Magnetic Resonance (NMR)Fundamental principles of Nuclear Magnetic Resonance (NMR)

Spin echo signal of an oil sample occuring 10 ms(echo time) after a 90° HF pulse (FID signal isshown). To generate the echo signal a 180° HFpulse has to be switched after half the echotime.



62

PrinciplePrinciple

The principles of relaxation processes using the MR technology aredemonstrated. Experiments are executed with the MRT trainingdevice giving the opportunity to investigate some small probes inthe sample chamber. Device control is done with the providedsoftware. Investigations comprise the estimation of the relaxationtime T1 which is a measure of time for reestablishing the longit-udinal magnetization, the measurement of this latter time andthe measurement of the relaxation time T2 which is a measure oftime for the decline of the transverse magnetization. T1 and T2 arespecific to the sample material and thus give important evidencefor the composition of the subject of investigation.

TasksTasks

1. Estimation of the relaxation time T1 via two successive 90°HF pulses.

2. Measuring the relaxation time T1 using an automatic soft-ware routine.

3. Measuring the relaxation time T2 using an automatic soft-ware routine.


▪ Nuclear spins; Precession of nuclear spins;Resonance condi-tion; MR frequency; MR flip angle

▪ Longitudinal and transverse magnetization; FID signal (FreeInduction Decay)

▪ T1/T2 relaxation times; Measuring T1/T2 relaxaion times; Spin-lattice relaxation (T1); Spin-spin relaxation (T2); Dephasing


Compact MRT 09500-99 1

Laboratory Experiments Magnetic ResonaceLaboratory Experiments Magnetic ResonaceTomography (MRT)Tomography (MRT)

DescriptionDescription

Comprehensive collection of experiments ragarding the magneticresonance (MR) technology. The manual comprises basic experi-ments of the MR physics as well as experiments on complex MRimaging (2D and 3D). Experiments are didactically and preciselyprepared and convey all relevant information about magnetic res-onance tomography.

Through questions, answers, evaluations and a comprehensivetheory students are guided and are able to learn one of the mostimportant procedures of medical diagnostics with a lot of fun andenjoyment. The software needed to perform the experiments per-fectly fits the experimental literature and thus enables an uniquelearning and teaching experience. For example parameters can bedirectly varied during a measurement ("on runtime").The manual is suitable for almost all fields of science. However,basically it is aimed at students with a deep medical background.

01233-0201233-02

P5942200P5942200Relaxation times in Nuclear Magnetic ResonanceRelaxation times in Nuclear Magnetic Resonance

Measurement of the T1 relaxation of an oilsample.



63

PrinciplePrinciple

Model experiment for electron spin resonance for clear demon-stration of interaction between the magnetic moment of the elec-tron spin with a superimposed direct or alternating magneticfield.


▪ Magnetic field▪ Precession frequency▪ Gyroscope▪ Magnetic induction


Gyroscope w.magn.axis,ESR model 11208-00 1

Variable transformer, 25 VAC/ 20 VDC, 12 A 13531-93 1

Blower 230V/50Hz 13770-97 1

Coil, 1200 turns 06515-01 4

Commutator switch 06034-03 1

On/off switch 06034-01 1

Iron core, short, laminated 06500-00 2

Variable transformer, 25 VAC/ 20 VDC, 12 AVariable transformer, 25 VAC/ 20 VDC, 12 A


Standard heavy duty power supply unit for low voltage.

Supply unit for continuously adjustable DC and AC voltages & 2 fre-quently required fixed voltages.


▪ AC output: 0...25 V/12 A▪ DC output: 0...20 V/12 A▪ Max. current (short term): 13 A▪ Add. fixed voltages: 6 V AC / 6 A, 12 V AC / 6 A▪ Max. current (short term): 10 A▪ Max. power: 375 VA▪ Fuses: one 13 A and two 10 A▪ Supply voltage: 230 V AC▪ Dimensions (mm): 230 x 236 x 234

13531-9313531-93

P2511205P2511205 Model experiment NMR / ESRModel experiment NMR / ESR

Gyroscope with magnetic axis, ESR model.



64

Measurespec spectrometer with cuvetteMeasurespec spectrometer with cuvetteholder and light sourceholder and light source


This set consisting of a Measurespec spectrometer (35610-00) anda cuvette holder and light source for the Measurespec (35610-99)makes it possible to record both emission and absorption spectra.

The light to be investigated is guided by optical fibres to a gridfixed inside the spectrometer, which disperses it into its spectralcolours. The spectrum is recorded with the aid of a CCD array,which records the entire spectrum at once, making it possible toreliably record rapid changes in the spectrum itself. The spectracan be displayed and stored by means of the supplied softwarewith its versatile functionality.

The spectrometer is connected to a PC via a USB port, which alsosuffices to supply power to the spectrometer, so that no addition-al supply is needed. The cuvette holder holds standard cuvettesmeasuring 1 cm x 1 cm. The built-in light source makes it pos-sible to record absorption spectra for solutions. The rapid meas-uring rate of the spectrometer even allows the speed of reactionsinvolving changes in colour to be measured (reaction kinetics).

Light having passed through the cuvette is guided into the spec-trometer via optical fibre. Fibres for fluorescence measurementscan also be attached at 90° to the path of the incident light.

BenefitsBenefits

Spectrometer:

▪ Robust aluminium case▪ Rapid measurement of full spectral range▪ Flexible introduction of light to be investigated by means of

optical fibres▪ No additional power supply required

▪ Measurement of emission spectra and absorption spectra▪ Intuitive "measure" software for controlling the apparatus

and recording spectra

Cuvette holder:

▪ Robust aluminium case▪ Long-lived tungsten lamp▪ Flexible introduction of light to be investigated by means of

optical fibres▪ Universal power supply via plug-in transformer▪ Measurement of absorption spectra, fluorescence spectra, re-

action kinetics


Spectrometer:

▪ Supplied with software and optical fibres▪ Range of wavelengths: 350...850 nm▪ Detector: silicon CCD array▪ Resolution: 4 nm▪ Connection to computer: USB▪ Optical fibre connection: SMA 905▪ Dimensions (mm): 170 x 126 x 55

Cuvette holder:

▪ Supplied with plug-in power supply and optical fibres▪ Type of lamp: tungsten (lifetime approx. 2000 hours)▪ Optical fibres: 50 µm x 2 m▪ 2 optical fibre connectors: SMA 905▪ Size of cuvettes: 1 cm x 1 cm▪ Power supply: 100 ... 240 V / 50 ... 60 Hz▪ Dimensions (mm): 95 x 51 x 46


Matching cuvettes:

▪ Cuvettes for spectral photometer, optical glass, 12 x 12 x 45mm, set of 2 (35664-02)

▪ Polystyrene macro-cuvette, 12 x 12 x 44 mm, 4 ml, set of 100(35663-10)

35610-8835610-88

Representation of a spectrum in "measureSpec"Representation of a spectrum in "measureSpec"

5 Spectroscopy5 Spectroscopy5.3 Photometry and Photochemistry


65

P3070101P3070101

PrinciplePrinciple

The structures of molecules are not changed by their chemicalenvironment in the gas phase. In contrast to this, on transitionto the condensed phase, in dilute solution, the solvent changesthe binding state of the dissolved substance. One of the way thisinfluence makes itself shown is in the elctron spectrum (solvato-chromatic shift).

Absorption of light (UV-VIS spectroscopy)Absorption of light (UV-VIS spectroscopy)


P3070301P3070301

PrinciplePrinciple

The position of the longest wavelength π - π* -absorption band inthe UV-VIS spectrum of organic compounds which have chromo-phoric systems can be approximately calculated by various meth-ods. For dyes with extended conjugated π-systems, the model ofthe electron in an unidimensional potential box (confinementregion) supplies results that agree sufficiently well with experi-mental results.

Excitation of moleculesExcitation of molecules


P3070401P3070401

PrinciplePrinciple

For weak acids HA, the position of the Ka and pKa values thatcharacterise the dissociation equilibrium in the ground statecan be determined from photometric measurements in solutionshaving different pH values. Further to this, the pKa* value for theexcited state is accessible from the spectrophotometric data.

Absorption spectra and pKa values of p-methoxyphenolAbsorption spectra and pKa values of p-methoxyphenol


5 Spectroscopy5 Spectroscopy5.3 Photometry and Photochemistry


66

68687575777780809393

101101117117125125

Physical ChemistryPhysical Chemistry6.16.1 Gas LawsGas Laws6.26.2 Kinetic TheoryKinetic Theory6.36.3 ViscosityViscosity6.46.4 Thermochemistry / CalorimetryThermochemistry / Calorimetry6.56.5 Chemical KineticsChemical Kinetics6.66.6 Electro ChemistryElectro Chemistry6.76.7 Phase EquilibriumPhase Equilibrium6.86.8 Atomic Structures and PropertiesAtomic Structures and Properties

6 Physical Chemistry6 Physical Chemistry


67

6 Physical Chemistry6 Physical Chemistry6.1 Gas Laws


68



69

PrinciplePrinciple

The state of a gas is determined by temperature, pressure andamount of substance. For the limiting case of ideal gases, thesestate variables are linked via the ideal gas law. For a change ofstate under isobaric conditions this equation converts Gay-Lussac'sfirst law.

TasksTasks

1. Experimentally investigate the validity of Gay-Lussac's law fora constant amount of gas (air).

2. Calculate the universal gas constant and the thermal coeffi-cient of expansion from the relationship obtained.


▪ Pressure▪ Temperature▪ Volume▪ Coefficient of thermal expansion▪ Ideal gas law▪ Universal gas constant▪ Gay-Lussac's law


Set Gas laws with glass jacket system andCobra4 43020-00 1

Cobra4 Remote-Link 12602-00 1

Johannes Diderik van der WaalsJohannes Diderik van der Waals


P3011160P3011160 Gay-Lussac's law (with Cobra4)Gay-Lussac's law (with Cobra4)

Volume in dependence on temperature.



70

PrinciplePrinciple

The state of a gas is determined by temperature, pressure andamount of substance. For the limiting case of ideal gases, thesestate variables are linked via the ideal gas law. For a change ofstate under isochoric conditions this equation becomes Amontons'law.

TasksTasks

1. Experimentally investigate whether Amontons' law is validfor a constant amount of gas (air).

2. From the resulting relationship calculate the universal gasconstant and thermal coefficient of tension.


▪ Pressure▪ Temperature▪ Volume▪ Thermal tension coefficient▪ Ideal gas law▪ Universal gas constant▪ Charles's (Amontons') law




Cobra4 Remote-LinkCobra4 Remote-Link


The Cobra4 Remote-Link is used to control the measuring value re-cording of an experiment constructed using a radiobased Cobra4network.

BenefitsBenefits

▪ The measuring value recording start and stop command istransmitted by radio to the Cobra4 Wireless Manager on thePC.

▪ Optimum application, e.g. in student experiments, free fallwith an acceleration sensor etc. .

12602-0012602-00

P3011260P3011260Amontons' law (with Cobra4)Amontons' law (with Cobra4)

Dependence of the pressure on the temperatureunder isochoric conditions.



71

PrinciplePrinciple

The state of a gas is determined by temperature, pressure andamount of substance. For the limiting case of ideal gases, thesestate variables are linked via the ideal gas law. In the case of iso-thermal process control this equation converts Boyle andMariotte's law.

TasksTasks

1. Experimentally investigate the validity of Boyle and Mariotte'slaw for a constant amount of gas (air).

2. From the resulting relationship calculate the universal gasconstant.


▪ Pressure▪ Temperature▪ Volume▪ Cubic compressibility coefficient▪ Ideal gas law▪ Universal gas constant▪ Boyle and Mariotte's law




Set Gas laws with glass jacket system andSet Gas laws with glass jacket system andCobra4Cobra4


Complete device compilation for a comfortable way to derive theideal gas laws experimentally with help of the Cobra4 Senor-UnitThermodynamics and the glass jacket system.


The set consists of:

▪ 1 Cobra4 Wireless Manager; 1 Cobra4 Wireless-Link.▪ 1 Cobra4 Sensor-Unit Thermodynamics, pressure absolute 2

bar and 2 x temperature.▪ 1 Software measure Cobra4, single user and school licence.▪ 1 Glass jacket; 1 Gas syringe 100 ml; 1 Heater for Glass jacket.▪ 1 Immersion probe NiCr-Ni, -50...1000 °C.▪ All necessary support materials and all the other small hard-

ware items to be able to carry out the measurements for thegas laws.

43020-0043020-00

P3011360P3011360 Boyle's law (with Cobra4)Boyle's law (with Cobra4)

Correlation between volume and pressure underisothermic conditions.



72

PrinciplePrinciple

According to Gay-Lussac's law of chemical volumes, gases react involume ratios which are whole numbers. These values can be volu-metrically determined.

TaskTask

Determine the volume ratio for the conversion of hydrogen andoxygen to water experimentally by burning gas mixtures of differ-ent compositions and measuring the resulting gas volume.


▪ Law of constant proportions▪ Avogadro's law▪ Gay-Lussac's law of chemical volumes▪ General equation of state for ideal gases▪ Gay-Lussac's first law



Slow eudiometer 02612-00 1







High voltage supply unit, 0-10 kVHigh voltage supply unit, 0-10 kV


For electrostatic experiments and for operation of spectral and gasdischarge tubes.


▪ It supplies 3 continuously variable DC voltages isolated fromearth and ground.

▪ Two of the voltages are connected in series 0-5 kV DC = totalof 0 -10 kV DC.

13670-9313670-93

P3031401P3031401Law of integer ratio of volumes according to Gay-Lussac's law ofLaw of integer ratio of volumes according to Gay-Lussac's law ofchemical volumeschemical volumes

Dependence of the final volume reduced toroom temperature from the initial volume ofhydrogen-oxygen mixtures of different composi-tion.

Thermal equation of state and critical pointThermal equation of state and critical point

P2320400P2320400



73

Handbook Glass Jacket SystemHandbook Glass Jacket System

Article no. 01196-12Article no. 01196-12


Comprehensive set of 17 experiments using the glass jacket set forvarious uses.

TopicsTopics

▪ Gas laws▪ Gas reactions▪ Determining molecular mass▪ Calorimetry▪ Gas chromatography▪ Distillation of steam

This system consists of a glass jacket, special inserts and accessor-ies. It was mainly developed for experiments with gases and canbe used at school for teaching physics, chemistry and biology.

▪ Demonstrative and transparent▪ Versatile and easily assembled▪ Water bath for accurate measurements

This documentation contains the following experiments:This documentation contains the following experiments:

Gay-Lussac's lawP1222900P1222900

Charles's (Amontons') lawP1223000P1223000

The Boyle-Mariotte lawP1223100P1223100

The gas laws of Boyle-Mariotte, Gay-Lussac and Charles(Amontons)P1223200P1223200

Determination of molar masses with the vapour density methodP1223301P1223301

Law of integer ratio of volumesP1223400P1223400

Gay-Lussac's law of volumesP1223551P1223551

Avogadro's lawP1223651P1223651

The empirical formula of methane, ethane and propaneP1223751P1223751

Determination of the heat of formation of waterP1223800P1223800

Determination of the heat of formation of CO2 and CO and Hess'slawP1223900P1223900

Determination of the heating values of solid and gaseous fuels ina horizontal calorimeterP1224051P1224051

Determination of the calorific value of food stuffsP1224100P1224100

Determination of the heating values of liquids in a verticalcalorimeterP1224251P1224251

Determination of the heating value of fuel oil and of the calorificvalue of olive oilP1224300P1224300

Chromatographic separation processes: Gas chromatographyP1224451P1224451

Steam distillationP1224551P1224551

01196-1201196-12

Steam distillation - P3031251Steam distillation - P3031251



74

PrinciplePrinciple

By means of the model apparatus for kinetic theory of gasesthe motion of gas molecules is simulated and the velocities de-termined by registration of the throw distance of the glass balls.This velocity distribution is compared to the theoretical Maxwell-Boltzmann equation.

TasksTasks

1. Measure the velocity distribution of the "model gas".2. Compare the result to theoretical behaviour as described by

the Maxwell-Boltzmann distribution.3. Discuss the results.


▪ Kinetic theory of gases▪ Temperature▪ Gas-molecules▪ Model kinetic energy▪ Average velocity▪ Velocity distribution


Kinetic gas theory apparatus 09060-00 1

Digital stroboscope 21809-93 1

Receiver with recording chamber 09061-00 1

Power supply variable 15 VAC/ 12 VDC/ 5 A 13530-93 1

Tripod base PHYWE 02002-55 2

Stopwatch, digital, 1/100 s 03071-01 1

Kinetic gas theory apparatusKinetic gas theory apparatus


Kinetic gas theory apparatus with vertical chamber and built inmotor.


▪ Chamber (mm) 60 x 20 x 180▪ Motor supply 12 VDC /20 W

09060-0009060-00

P2320300P2320300Maxwellian velocity distributionMaxwellian velocity distribution

Experimental and theoretical velocity distribu-tion in the model experiment.

6 Physical Chemistry6 Physical Chemistry6.2 Kinetic Theory


75

PrinciplePrinciple

Diffusion arises from the flow of matter down a concentrationgradient. In the evaporation method, a stationary concentrationgradient is achieved in which the concentration decreases linearlywith distance. Under these conditions the diffusion coefficient ofthe diffusing substance may be calculated by a direct applicationof Fick's first law of diffusion.

TaskTask

Measure the diffusion coefficient of bromine in air using anevaporation method.


▪ Kinetic theory of gases▪ Transport properties▪ Fick's laws of diffusion▪ Self and mutual diffusion coefficients▪ Alternative techniques e.g. Loschmidt's method



Tube connector, T-shaped, IGJ29 35859-00 1


Bromine 100 ml 30046-10 1

Gas-wash.bottle w.frit, IGJ.29/32 36691-01 1


P3010301P3010301 Diffusion in gases: The diffusion coefficient of bromine in airDiffusion in gases: The diffusion coefficient of bromine in air

Diffusion coefficient of Fick's first law.

6 Physical Chemistry6 Physical Chemistry6.2 Kinetic Theory


76

PrinciplePrinciple

The viscosity of liquids can be determined with a rotation vis-cometer, in which a motor with variable rotation speed drives acylinder immersed in the liquid to be investigated with a spiralspring. The viscosity of the liquid generates a moment of rotationat the cylinder which can be measured with the aid of the torsionof the spiral spring and read on a scale.

TasksTasks

1. Determine the gradient of the rotational velocity as a func-tion of the torsional shearing stress for two Newtonian li-quids (glycerine, liquid paraffin).

2. Investigate the temperature dependence of the viscosity ofCastor oil and glycerine.

3. Determine the flow curve for a non Newtonian liquid (chocol-ate).


▪ Shear stress; Velocity gradient; Internal friction▪ Viscosity; Plasticity


Rotary viscometer, 15 - 2,000,000 mPas,110...240 V 18223-99 1



Glycerol 250 ml 30084-25 2

Castor oil 250 ml 31799-27 2

Liquid paraffin 250 ml 30180-25 1

Acetone, chem.pure 250 ml 30004-25 3

Rotary viscometer, 15 - 2,000,000 mPas,Rotary viscometer, 15 - 2,000,000 mPas,110...240 V110...240 V


Classic rotational viscometer for the viscosity determination ac-cording to ISO2555 ("Brookfield method") and many ASTM stand-ards.

BenefitsBenefits

▪ The results are 100% compatible to the Brookfield method.▪ All results (viscosity, torque in %, speed, spindle) are displayed

on the built-in display.▪ Multilanguage display: English, French, German, Spanish,

Italian, Japanese, Portuguese, Dutch, Polish, Catalan.▪ Visual and acoustic signals at critical measuring conditions.▪ Warning, if the device is used outside of the permissible meas-

uring ranges.▪ Digital speed control with "built-in"accuracy through stepping

motor.▪ Touchless, optoelectronic torque measuring system with high

accuracy and without wear.▪ It is supllied as a complete measuring unit consisting of the

basic instrument with stand, set of spindles with a storagerack in a stable case.

18223-9918223-99

P2140300P2140300Viscosity of Newtonian and non-Newtonian liquids (rotaryViscosity of Newtonian and non-Newtonian liquids (rotaryviscometer)viscometer)

Moment of rotation as a function of the fre-quency for a Newtonian liquid Glycerine(+), Liquid paraffin(o).

6 Physical Chemistry6 Physical Chemistry6.3 Viscosity


77

PrinciplePrinciple

Due to internal friction among their particles, liquids and gaseshave different viscosities. The viscosity, a function of the sub-stance's structure and its temperature, can be experimentally de-termined, for example, by measuring the rate of fall of a ball in atube filled with the liquid to be investigated.

TasksTasks

Measure the viscosity

1. of methanol-water mixtures of various composition at a con-stant temperature,

2. of water as a function of the temperature and3. of methanol as a function of temperature.

From the temperature dependence of the viscosity, calculate theenergy barriers for the displace ability of water and methanol.


▪ Newtonian liquid▪ Stokes law; Fluidity▪ Dynamic and kinematic viscosity▪ Viscosity measurements


Falling ball viscometer 18220-00 1


Thermometer, 24...+ 51 ºC, for 18220.00 18220-02 1

Bath for thermostat, makrolon 08487-02 1



Falling ball viscometerFalling ball viscometer


Falling ball viscometer.


▪ Thermometer▪ Diameter of the fall tube: 15.95 mm▪ Initiable fall times: 25...300 s▪ Fall distance: 100 mm▪ 6 balls

18220-0018220-00

P2140400P2140400 Viscosity measurement with the falling ball viscometerViscosity measurement with the falling ball viscometer

Temperature dependence of the dynamicviscosity of water (o) and methanol (+), respect-ively.



78

PrinciplePrinciple

The viscosity of a liquid is effectively determined by the strengthof the intermolecular attractive forces. In the case of solutions,the viscosity of the solvent can alter significantly depending onthe type and concentration of the solute. Due to their size, macro-molecules have a very considerable impact on the viscosity of thesolvent. Viscosity measurements can be used to estimate the meanmolecular mass of a macromolecule if something is known aboutits conformation.

TasksTasks

1. Use a thermostatted capillary viscometer to measure the vis-cosities of solutions of polystyrene in toluene over a range offive polymer concentrations.

2. Determine the instrinsic viscosity and from that estimate themolecular weight (relative molecular mass) of the polymer inthis solution.


▪ Viscosity of liquids▪ Ostwald capillary viscometer▪ Poiseuilles's equation▪ Macromolecules▪ Mass average and number average molecular weights▪ The Mark-Houwink equation▪ Alternative techniques e.g. osmosis▪ Sedimentation (ultracentrifuge methods)▪ Light scattering



Ubbelohde viscosimeter, 0.4 mm 03102-03 1




Water jet pump, plastic 02728-00 1


P3010601P3010601Determining the molecular weight of a polymer from intrinsicDetermining the molecular weight of a polymer from intrinsicviscosity measurementsviscosity measurements

Plot used to determine the intrinsic vicosity h.Data for polystyrene in toluene at 25.0°C.



79

PrinciplePrinciple

A mass oscillates on a volume of gas in a precision glass tube. Theoscillations maintained by leading escaping gas back into the sys-tem. The adiabatic coefficient of various gases is determined fromthe periodic time of the oscillation.

TaskTask

Determine the adiabatic coefficient of air, nitrogen and carbon di-oxide (and also of argon, if available) from the periodic time of theoscillation T of the mass on the volume V of gas.


▪ Equation of adiabatic change of state▪ Polytropic equation▪ Rüchardt's experiment▪ Thermal capacity of gases


Steel cylinder,CO2, 10l, full 41761-00 1

Steel cylinder,nitrogen,10l, full 41763-00 1

Light barrier with counter 11207-30 1

Gas oscillator, Flammersfeld 04368-00 1

Sliding weight balance, Kern 150-23, 101 g /0.01 g 44012-01 1

Reducing valve for CO2 / He 33481-00 1

Reducing valve f. nitrogen 33483-00 1

Light barrier, compactLight barrier, compact


Universal fork-type light barrier to measure short and long shad-owing periods.

BenefitsBenefits

▪ An incremental wheel with a string groove which can be at-tached to the fork of the light barrier allows to measure pathsby counting the ribs of the incremental wheel.

▪ Areas of application: track experiments, freefall, pendulumexperiments, leaf spring oscillations, drop counters, volumet-ric measurements concerning the gas laws.


▪ Dimensions: 40 x 40 mm▪ Supply voltage: 5 V

11207-2011207-20

P3020260P3020260 Adiabatic coefficient of gases - Flammersfeld oscillatorAdiabatic coefficient of gases - Flammersfeld oscillator

Sample results for the adiabatic coefficients. Ex-perimental conditions: ten measurements, eachof about n = 300 oscillations.

6 Physical Chemistry6 Physical Chemistry6.4 Thermochemistry / Calorimetry


80

PrinciplePrinciple

Heat is added to a gas in a glass vessel by an electric heaterwhich is switched on briefly. The temperature increase results ina pressure increase, which is measured with a manometer. Underisobaric conditions a temperature increase results in a volumedilatation, which can be read from a gas syringe. The molar heatcapacities Cv and Cp are calculated from the pressure or volumechange.

TaskTask

Determine the molar heat capacities of air at constant volume Cvand at constant pressure Cp.


▪ Equation of state for ideal gases▪ First law of thermodynamics▪ Universal gas constant▪ Degree of freedom▪ Mole volumes▪ Isobars▪ Isotherms▪ Isochors and adiabatic changes of slate


Universal Counter 13601-99 1

Precision manometer 03091-00 1

Weather station, wireless 04854-00 1

Mariotte flask, 10 l 02629-00 1



Two-way switch, single pole 06030-00 1

Universal CounterUniversal Counter


The universal counter is used for measuring time, frequency, pulserates, pulse counting, periodic times, speeds and velocities.

BenefitsBenefits

▪ The device has all the qualities that are expected of a modernuniversal counter and is also equiped with a number of tech-nical specifics of how it specifically arise from the require-ments of science teaching practice.

▪ For the scientifically correct representation of each measure-ment is shown in principle with the associated unit. With theoverflow of the display is automatically switched into the nextarea.

▪ Before the measurement starts it can be manually adjusted toa maximum of 6 decades defined range, e.g. to suppress is notphysically meaningful digits on the display.

▪ A special jack for direct connection of a GM counter tube isavailable for radioactivity experiments. The required voltagecan be changed manually to determine the characteristics ofa counter tube too.

13601-9913601-99

P2320201P2320201Heat capacity of gasesHeat capacity of gases

Pressure change p as a function of the heat-uptime t. U = 4.59 V, I = 0.43 A.



81

PrinciplePrinciple

The vaporisation of a liquid occurs with heat absorption. To de-termine the enthalpy of vaporisation, a known mass of the liquidwhich is to be investigated is vaporised in a special vaporisationvessel in a current of air. The quantity of heat absorbed, whichcorresponds to the enthalpy of vaporisation, can be calorimetric-ally determined.

TasksTasks

1. Determine the molar enthalpy of vaporisation of diethyl eth-er and methanol.

2. Calculate the molar entropies of vaporisation and discuss theresults under consideration of Trouton's rule.


▪ Enthalpy of vaporisation▪ Enthalpy of condensation▪ Enthalpy of sublimation▪ Vapour pressure; Entropy of vaporization▪ Clausius-Clapeyron equation; Trouton's rule▪ Law of thermodynamics; Calorimetry




Evaporation vessel for calorimeter 04405-00 1

Set of Precisionl Balance Sartorius CPA 6202Sand measure software, 230 V 49226-88 1



Work and power meterWork and power meter


For AC and DC circuits


▪ Two 4-digit, 20 mm LED-displays; Display 1 for real and ap-parent power,current, voltage, phase difference and freqency

▪ Display 2 for energy and time;Selector for serial display ofall units; LED-Status-display and automactic range selection;Power: max. 2400 W; Resolution: max. 0.001 W

▪ Voltage: 0-30V AC/DC, 0-240 V; eff- Current: 0...10A AC/DC

13715-9313715-93

P3020411P3020411 Determination of the enthalpy of vaporisation of liquids (withDetermination of the enthalpy of vaporisation of liquids (withCobra3)Cobra3)

Temperature-time curve of the vaporisation ofdiethyl ether and determining the heat capacityof the system.

Determination of the enthalpy of vaporisation of liquidsDetermination of the enthalpy of vaporisation of liquids(with Cobra4)(with Cobra4)

P3020460P3020460



82

PrinciplePrinciple

Due to intermolecular interactions, the total volume measuredwhen two real liquids (e.g. ethanol and water) are mixed deviatesfrom the total volume calculated from the individual volumes ofthe two liquids (volume contraction). To describe this non-idealbehaviour in the mixing phase, one defines partial molarquantities which are dependent on the composition of the system.The values of these can be experimentally determined.

TasksTasks

1. Measure the densities of different ethanol-water mixtures ofspecified composition at 20 °C with pycnometers.

2. Calculate the real volumes and the mean molar mixingvolumes of the investigated ethanol-water mixtures and alsothe partial molar volumes of each liquid for selected compos-itions.

3. Compare them with the molar volumes of the pure sub-stances at 20 °C.


▪ Principles of thermodynamics▪ Ideal and non-ideal behaviour of gases and liquids▪ Volume contraction▪ Molar and partial molar quantities





Pycnometer, calibrated, 25 ml 03023-00 9


Immersion thermostat Alpha A, 230 VImmersion thermostat Alpha A, 230 V


Immersion circulator with simple, reliable options for obtainingconsistent results. Compact unit can be combined with any exist-ing baths up to 25 mm wall thickness.

BenefitsBenefits

▪ Wide temperature range to meet application needs.▪ Digital settings for simple operation.▪ Strong pump for high temperature conformity.▪ To be used with water as heat transfer liquid.▪ Screw clamp for bath walls up to 25 mm.▪ Robust design using high grade stainless steel and temperat-

ure resistant polymer.▪ Wear-free; integrated overload protection.

08493-9308493-93

P3020501P3020501Partial molar volumesPartial molar volumes

Dependence of the mean molar mixingvolumes on the composition of differentethanol/water mixtures.



83

PrinciplePrinciple

When two miscible liquids are mixed, a positive or negative heateffect occurs, which is caused by the interactions between the mo-lecules. This heat effect is dependent on the mixing ratio. The in-tegral mixing enthalpy and the differential molar mixing enthalpycan be determined by calorimetric measurements of the heat ofreaction.

TasksTasks

1. Measure the integral mixing enthalpy of seven differentwater-acetone mixtures.

2. Plot the molar integral mixing enthalpy versus the quantityof substance (mole fraction) and determine the molar mixingenthalpy.

3. Discuss the results on the basis of the interactions in the mix-ture.


▪ Differential molar mixing enthalpy▪ Real and ideal behaviour▪ Integral molar mixing enthalpy▪ Fundamental principles of thermodynamics▪ Calorimetry








Set calorimetry, 230 VSet calorimetry, 230 V


With this setup a great number of measurements to heat capa-cities, reaction enthalpies, solution enthalpies, neutralisation en-thalpies, melting enthalpies and enthalpies of mixtures can becarried out.

43030-8843030-88

P3020611P3020611 Determination of the mixing enthalpy of binary fluid mixturesDetermination of the mixing enthalpy of binary fluid mixtures(with Cobra3)(with Cobra3)

Temperature-time curve of the mixing of twomiscible fluids and determining the heat capa-city of the system.

Determination of the mixing enthalpy of binary fluidDetermination of the mixing enthalpy of binary fluidmixtures (with Cobra4)mixtures (with Cobra4)

P3020660P3020660



84

PrinciplePrinciple

When a solid electrolyte dissolves in water, a positive or negativeheat effect occurs as a result of the destruction of the crystal lat-tice and the formation of hydrated ions. The enthalpy of hydrationof copper sulphate can be calculated from the different heats ofreaction measured when anhydrous and hydrated copper sulphateare separately dissolved in water.

TasksTasks

1. Record temperature-time curves for the dissolution of an-hydrous copper(II) sulphate and hydrated copper(II) sulphatein water.

2. Calculate the hydration enthalpy of anhydrous copper(II)sulphate.


▪ Integral enthalpy of solution▪ Hess' law▪ Lattice energy▪ Ion solvation▪ Calorimetry




Desiccator, wertex, diam. 150 mm 34126-00 1

Butane burner, Labogaz 206 type 32178-00 1

Silica gel, orange, granular, 500 g 30224-50 1

Copper-II sulphate, anhydr. 250 g 31495-25 1




P3020711P3020711Determination of the hydration enthalpy of an electrolyteDetermination of the hydration enthalpy of an electrolyte(solution enthalpy) (with Cobra3)(solution enthalpy) (with Cobra3)

Temperature-time curves of solutions of anhyd-rous and hydrated copper sulphate and determ-ining the heat capacity of the system.

Determination of the enthalpy of neutralisation (withDetermination of the enthalpy of neutralisation (withCobra3)Cobra3)

P3020811P3020811

Determination of the hydration enthalpy of an electrolyteDetermination of the hydration enthalpy of an electrolyte(solution enthalpy) (with Cobra4)(solution enthalpy) (with Cobra4)

P3020760P3020760



85

PrinciplePrinciple

When a solid melts, energy is required for the destruction of thecrystal lattice. A substance whose melting point lies slightly belowroom temperature is first cooled until it solidifies and then meltedin a calorimeter. The melting enthalpy is calculated from the de-crease in temperature due to the melting process which is meas-ured in the calorimeter.

TasksTasks

1. Take a temperature-time-diagram for the melting process ofdioxan.

2. Calculate the melting enthalpy and entropy of 1,4-dioxan.


▪ Heat capacity▪ Melting point▪ Latent heat▪ Calorimetry▪ Gibbs' phase rule▪ Enthalpy of sublimation▪ Enthalpy of vaporisation




Dewar vessel,500 ml 33006-00 1

Dioxane 1000 ml 31266-70 1

Separator for magnetic bars 35680-03 1



P3020911P3020911 Determination of the melting enthalpy of a pure substance (withDetermination of the melting enthalpy of a pure substance (withCobra3)Cobra3)

Temperature-time curve for the melting processof dioxan and determining the heat capacity ofthe system.

Determination of the melting enthalpy of a pureDetermination of the melting enthalpy of a puresubstance (with Cobra4)substance (with Cobra4)

P3020960P3020960



86

PrinciplePrinciple

The bomb calorimeter is used to completely burn substances in anexcess of oxygen. The heat of combustion released is absorbed bythe calorimetric vessel in which the bomb is immersed, and res-ults in a temperature increase ΔT. The heat capacity of the systemis first determined by adding a defined amount of heat from thecombustion of benzoic acid. The combustion of the naphthalene issubsequently performed under the same conditions.

TasksTasks

1. Determine the enthalpy of combustion of naphtalene using abomb calorimeter.

2. Calculate the enthalpy of formation of naphthalene from theenthalpy of combusting unsing Hess' law.


▪ First law of thermodynamics▪ Hess' law of constant heat summation▪ Enthalpy of combustion▪ Enthalpy of formation▪ Heat capacity


Calorimetric bomb 04403-00 1




Calorimeter, transparent, volume appr. 1200ml 04402-00 1



Calorimetric bombCalorimetric bomb


Calorimetric bomb for the quantitative determination of combus-tion heat of liquid and solid organic substances under high oxygenpressure.


▪ Stainless steel body▪ Contents approx. 120 ml▪ Stainless steel lid with valve▪ Oxygen filling connection▪ Max. oxygen pressure 25 bar▪ Ignition wire

04403-0004403-00

P3021401P3021401Determination of the enthalpy of combustion with a calorimetricDetermination of the enthalpy of combustion with a calorimetricbombbomb

Determining the corrected temperature differ-ence.



87

PrinciplePrinciple

Standard molar enthalpies of formation ΔBHΦ are important com-

piled thermodynamics tabulation quantities for calculating stand-ard enthalpies of reaction for any arbitrary reaction. They aredefined as the heat of reaction occurring in the direct formationof one mole of the pertinent pure substance from the stable pureelements at constant pressure. For spontaneous and quantitativeformation reactions, e.g. the conversion of hydrogen and oxygento water, standard enthalpies of formation can be measureddirectly using calorimetry.

TasksTasks

Determine the enthalpy of formation of water by burning 100 mlH2 in a closed glass jacket calorimeter.


▪ First law of thermodynamics▪ Thermochemistry▪ Calorimetry▪ Enthalpy of formation▪ Enthalpy of reaction





Lid for calorimeter insert 02615-02 1


Calorimeter insert for glass jacket 02615-01 1


Glass jacketGlass jacket


Glass jacket, used as cooling or heating mantle.

BenefitsBenefits

The cylinder is made of DURAN 50 ®, which gave him an extremeheat resistance, high thermal shock resistance, mechanicalstrength and excellent chemical resistance.


▪ Cylindrical glasstube with screw closures for different inserts▪ Length: 205 mm▪ Outer diameter: 75 mm▪ Connecting nut and gasket for flanging cylindrical inserts with

an outer diameter of 36 mm watertight and airtight▪ 1 Flange with ring nut

02615-0002615-00

P3021501P3021501 Determination of the heat of formation of waterDetermination of the heat of formation of water

General equation of state for ideal gases.



88

PrinciplePrinciple

The standard molar enthalpies of formation ΔBHΦ are important

compiled thermodynamic tabulation quantities for calculatingstandard enthalpies of reaction for any arbitrary reaction. They aredefined as the heat of reaction occurring in the direct formationof one mole of the pertinet pure substance from the stable pureelements at constant pressure. For spontaneous and quantitativeformation reactions, e.g. the conversion of carbon and oxygen toCO2, standard enthalpies of formation can be measured directlyusing calorimetry. Alternativly, they can be calculated from knownentahlpies of reaction using Hess' law.

TasksTasks

1. Determine the enthalpies of reaction for the combus-tion of carbon and carbon monoxide calometrically.

2. Use the experimentally determined enthalpies andHess' law to calculate the enthalpies of formation of COand CO2.


▪ First law of thermodynamics▪ Thermochemistry▪ Calorimetry▪ Enthalpy of formation▪ Enthalpy of reaction▪ Hess' law


Gasometer 1000 ml 40461-00 1





Reducing valve for oxygen 33482-00 1


Gasometer 1000 mlGasometer 1000 ml


Gasometer.


▪ Content 1000 ml▪ Adjustable outer scale▪ Readability 10 ml

40461-0040461-00

P3021601P3021601Determination of the heat of formation for CO2 and CO (Hess'Determination of the heat of formation for CO2 and CO (Hess'law)law)

Experimental setup for preparing the carbonmonoxide.



89

PrinciplePrinciple

The heat of reaction generated during the complete combustion of1000 g of solid or liquid fuel is known as the calorific value H. Inthe case of complete combustion of nutritional fats, the gross cal-orific value can also be determined. In order to ensure completecombustion, the reaction takes place under oxygen. The heat gen-erated during the combustion of a specific amount of fuel is ab-sorbed by a glass jacket calorimeter of known heat capacity. Thecalorific value of the test substance can be calculated from thetemperature increase in the calorimeter.

TaskTask

Determine the calorific value of heating oil and the gross calorificvalue of olive oil.


▪ Heat of reaction▪ Heat of combustion▪ Enthalpy of combustion▪ First law of thermodynamics








Calorimeter insert for glass jacketCalorimeter insert for glass jacket


Calorimeter insert for glass jacket.

BenefitsBenefits

▪ It can determine calorific values, heat of combustion and en-thalpies of gaseous, liquid and solid substances.

▪ Combustion chamber with a circular cross section, rotatingdouble helix as a heat exchanger


▪ Total length: 280 mm▪ Combustion chamber length: 90 mm▪ Outer combustion chamber: 36 mm▪ Length of the approach pipe: 70 mm▪ OD approach pipe: 8 mm

02615-0102615-01

P3021701P3021701 Determination of the heating value of fuel oil and of the calorificDetermination of the heating value of fuel oil and of the calorificvalue of olive oilvalue of olive oil

Equation to calculate the calorific value (offuels) and the gross calorific value (of food-stuffs).



90

PrinciplePrinciple

The volume expansion of liquids and the linear expansion variousmaterials is determined as a function of temperature.

TasksTasks

1. To determine the volume expansion of ethyl acetate(C4H8O2), methylated spirit, olive oil, glycerol and water as afunction of temperature, using the pycnometer.

2. To determine the linear expansion of brass, iron, copper, alu-minium, duran glass and quartz glass as a function of tem-perature using a dilatometer.

3. To investigate the relationship between change in length andoverall length in the case of aluminium.


▪ Linear expansion▪ Volume expansion of liquids▪ Thermal capacity▪ Lattice potential▪ Equilibrium spacing▪ Grüneisen equation



Dilatometer with clock gauge 04233-00 1


Tube, quartz for 04231-01 04231-07 1

Measuring tube, l = 300 mm, IGJ 19/26 03024-00 2

Aluminium tube for 04231-01 04231-06 1


Dilatometer with clock gaugeDilatometer with clock gauge


Dilatometer with clock gauge on baseplate 730x50x25 mm for thequantitative measurement of the linear expansion of solid bodiesdepending on material, length and temperature.

BenefitsBenefits

▪ Metal tubes are fixed on the base plate and heated by hot wa-ter or steam flowing through them.

▪ Base plate with fixing holder, leading bearing and measuringunit.

▪ Transmission of linear expansion to a pointer by means oftoothed rod and wheel.

04233-0004233-00

P2310100P2310100Thermal expansion in solids and liquidsThermal expansion in solids and liquids

Relationship between length l and temperature,for a) aluminium, b) brass, c) copper, d) steel, e)duran glass, f) quartz glass (lo = 600 mm).



91

PrinciplePrinciple

In general, the term adsorption is used to describe the attachmentof gases or dissolved substances to the surface of a solid or liquid.At constant temperature, the quantity of adsorbed substances is afunction of the type of system investigated and the partial pres-sure and / or concentration of the substance concerned. The cor-relation is described by a number of adsorption isotherms. Therivalidity is to be investigated experimentally.

TasksTasks

1. Determine the residual equilibrium concentrations of citricacid after stirring solutions of differing initial concentrationswith a constant mass of activated carbon.

2. Use the measurement results to determine which of the ad-sorption isotherms is valid for the given system.


▪ Adsorbent and adsorbate▪ Henry Freundlich and Langmuir adsorption isotherms▪ Volumetry



Filtration stand for 2 funnels 33401-88 1


Burette, lateral stopcock, Schellbach, 50 ml,graduations 0, 1 ml 36513-01 1




Irving LangmuirIrving Langmuir


P3040801P3040801 Adsorption isothermsAdsorption isotherms

Investigation of the adsorption isotherm for thecitric acid/active carbon system.



92

PrinciplePrinciple

Tertiary butylhalogenides are saponified in aqueous and aqueousbasic solutions according to an SN1 mechanism to tertiary butanol.The kinetics of the reaction can be followed via the temporal con-sumption of hydroxide ions and evaluated accordingly.

TasksTasks

1. Determine the concentration-time diagram for the saponi-fication of tert-butyl chloride with sodium hydroxide solu-tion.

2. Based on the experimental data, establish the valid reactionorder, and calculate the reaction rate constant and the half-life of the reaction.


▪ Reaction rate▪ Reaction rate constant▪ Molecularity of reaction▪ Reaction order▪ Rate law for first and second order reactions▪ Half-life



Digital thermometer, NiCr-Ni, -50...+1300 °C 07050-00 1

Immersion probe NiCr-Ni, steel, -50...400 °C 13615-03 1

tert-Butyl chloride, 250 ml 30045-25 1

Burette clamp, roller mount.,2 pl. 37720-00 1

Caustic soda sol.,1.0 M 1000 ml 48329-70 1


P3050101P3050101Saponification rate of tert-butyl chlorideSaponification rate of tert-butyl chloride

Concentration-time diagram for the saponifica-tion of tert-butyl chloride in acetone/water.

6 Physical Chemistry6 Physical Chemistry6.5 Chemical Kinetics


93

PrinciplePrinciple

The reaction velocity is highly dependent on the temperature. Inthis experiment magnesium reacts with acetic acid. Comparing thevelocity at the beginning of the reaction shows that the velocitydoubles when the temperature increases 10 K.

TaskTask

Investigate the reaction of magnesium with acetic acid at differ-ent temperatures.


▪ Reaction kinetics▪ First order reaction▪ Magnesium▪ Acid




Stop clock, demo.; diam. 13 cm 03075-00 1

Round flask, 100 ml, 3-n., 3 x GL25 35677-15 1


Magnesium, ribbon, roll, 25 g 30132-00 1


Magnetic stirrer MR Hei-StandardMagnetic stirrer MR Hei-Standard


Modern magnetic hot plate stirrer with a flat and hermeticallysealed housing as protection against chemicals.

BenefitsBenefits

▪ Separate switchers with LEDs for heating and stirring▪ Hot plate made of Silumin (aluminiumalloys) with ceramic

coating▪ Excellent heat conduction and distribution▪ Extremely resistant against scratches and chemicals

35750-9335750-93

P3051101P3051101 Dependence of the reaction velocity on the temperature (aceticDependence of the reaction velocity on the temperature (aceticacid - magnesium)acid - magnesium)

Schematical setup.



94

PrinciplePrinciple

In acid solution, ethyl acetate is hydrolysed to equivalent quant-ities of ethanol and acetic acid according to a pseudo-first orderrate law. The alkalimetric determination of the acetic acid formedenables conclusions to be drawn on the temporal concentration ofester.

TasksTasks

1. Determine the reaction rate constant for the acidolysis ofethyl acetate at two (or more) temperatures.

2. Calculate the activation energy of the reaction from the tem-perature dependence of the measured rate constants.


▪ Reaction rate▪ Reaction rate constant▪ Rate law for first and second order reactions▪ Reactions with pseudo order▪ Arrhenius equation▪ Activation energy









P3050201P3050201Reaction rate and activation energy of the acid hydrolysis ofReaction rate and activation energy of the acid hydrolysis ofethyl acetateethyl acetate

Graphic determination of the reaction rate con-stant for the acid hydrolysis of ethyl acetate at

Tx = 299.15 K and To = 314.15 K.



95

PrinciplePrinciple

The inversion reaction of saccharose, which is catalysed by pro-tons, produces invert sugar, which is a mixture of glucose andfructose. The reaction is accompanied by a change in the opticalrotation of the system. Glucose rotates the polarisation plane oflinearly polarised light to the right, while inverted sugar rotates itto the left. A half-shade polarimeter is used for the measurementof the change in the angle of rotation of polarised light during theinversion reaction of saccharose over time.

TasksTasks

1. Determine the specific rotation of saccharose and lactose bymeasuring the rotation angle of solutions of various concen-trations.

2. Determine the rate constant of the inversion of saccharose.


▪ Reaction rate▪ First order reaction▪ Polarimetry▪ Optical rotation


Half-shade polarimeter, 230 V AC 35906-93 1





Retort stand, 210 × 130 mm, h = 500 mm 37692-00 1


Half-shade polarimeter, 230 V ACHalf-shade polarimeter, 230 V AC


Half-shade polarimeter for concentration measurement of opticalactive solutions.


▪ Polarimeter support with built-inlight source and filters▪ Polarimeter tube length 100 and 200 mm▪ 2 scales 0-180 degrees▪ Division 1 degree▪ Vernier reading 0.05 degrees with nonius▪ Light source sodium lamp 589 nm▪ Power supply 230 V / 50 Hz

35906-9335906-93

P3050301P3050301 Kinetics of the inversion of saccharoseKinetics of the inversion of saccharose

Floating point representation of saccharose in-version as a function of time.



96

PrinciplePrinciple

Alkyl halides experience rapid halogen exchange reactions in ap-propriate solvents. These substitution reactions occur according toan SN2 mechanism. Their velocity can be advantageously mon-itored via conductivity measurements if the ion mobilities in ques-tion clearly differ, or the number of charge carriers changes in thecourse of the reaction.

TasksTasks

1. Measure the specific conductivities of solutions of variousconcentrations of sodium iodide in acetone.

2. Subsequently determine the temporal concentrations of theco-reactants for the reaction of propyl bromide with sodiumiodide (Finkelstein reaction) in acetone at 30 °C. Based onthe experimental data, establish the valid order of reactionand determine the rate constant.


▪ Reaction rate▪ Rate laws for first and higher order reactions▪ Conductometry












BenefitsBenefits

▪ Measure conductivity or temperature - multipurpose-sensor.▪ The Cobra4 sensor may be connected directly to the Cobra4


12632-0012632-00

P3050760P3050760Halogen exchange rate (with Cobra4)Halogen exchange rate (with Cobra4)

Concentration-time diagram (cPrBr = cI- = cNaI)for the Finkelstein reaction between propylbromide and iodide ions (T = 303 K).



97

PrinciplePrinciple

Carboxylic acid esters are saponified in an alkaline medium ac-cording to the second order reaction rate (law). In the process, hy-droxide ions with a high ion mobility are consumed in reactionwith an ester. The temporal course of reaction can thus be advant-ageously monitored by using the measurements of the changingconductance.

TasksTasks

Determine the reaction rate constant for the saponification ofethyl butyrate in an ethanol-water mixture at 50 °C via the con-ductance measurements.


▪ Reaction rate▪ Reaction rate constant▪ Reaction molecularity▪ Reaction order▪ First and second order reaction rates (laws)▪ Conductance and conductance measurements (conducto-

metry)





Software Cobra4 - multi user licence 14550-61 1



Condenser, Dimroth type GL25/12 35815-15 1

P3050860P3050860 Conductometric measurement of the saponification of estersConductometric measurement of the saponification of esters(with Cobra4)(with Cobra4)

Change in the specific conductivity k during thesaponification of ethyl butyrate in ethanol/wa-ter at an approximate ratio of 50:50 (T=323.15K).



98

PrinciplePrinciple

The Briggs-Rauscher reaction is a so-called homogeneous oscillat-ing reaction, i.e. the reaction rate of the complete process is sub-ject to periodic fluctuations. In general, oscillating reactions canalways occur when the following conditions are fulfilled: The re-action must run highly exergonic (ΔG << 0). At least one of thereaction steps must contain a positive or negative back-coupling.Such back-coupling processes occur when the result of the indi-vidual partial steps of the reaction, such as changes in temperat-ure or concentration, act back on the rate constants of the indi-vidual partial steps of the reaction. In this way, the whole reactionbecomes non-linear.

TaskTask

Observer the fluctuations of the Briggs-Rauscher reaction by meas-uring the potential over a definite time period.


▪ Oscillating reactions; Exergonic process▪ Potential; Briggs-Rauscher reaction








Cobra4 Sensor-Unit Chemistry, pH and 2 xCobra4 Sensor-Unit Chemistry, pH and 2 xTemperature NiCr-NiTemperature NiCr-Ni


The Cobra4 Sensor-Unit Chemistry is a measuring recorder for pH,potential and temperature measurements, which is controlled bymicro-controller.

BenefitsBenefits

▪ It can be fitted with two NiCr-Ni thermoelements (Type K) anda pH probe or redox measuring chain

▪ Values of the calibration are saved in the sensor - no need fornew calibration.

▪ The sensor is not restricted to the measurement of pH values:Connect the redox electrode 46267-10 to measure redox po-tentials.

12630-0012630-00

P3121660P3121660Briggs-Rauscher Reaction (with Cobra4)Briggs-Rauscher Reaction (with Cobra4)

Graph of measured potential against time.



99

P4120360P4120360

PrinciplePrinciple

The enzymatic hydrolysis of urea in aqueous solution liberatescarbon dixide and ammonia. The ions of these compounds in-crease the conductivity of the solution. Conductivity measure-ments can so be made to determine the rate of hydrolysis of ureaby the enzyme urease at various substrate concentrations.

Determination of the Michaelis constant (with Cobra4)Determination of the Michaelis constant (with Cobra4)


P4120560P4120560

PrinciplePrinciple

The enzymatic hydrolysis of urea in aqueous solutions liberatescarbon dioxide and ammonia. The ions of these compounds in-crease the conducitivity of the solution.

Enzyme inhibition (poisoning of enzymes) (with Cobra4)Enzyme inhibition (poisoning of enzymes) (with Cobra4)




100

PrinciplePrinciple

Measuring the temperature dependence of the resistivity of solidsprovides information on the mechanism of conduction and chargetransport in solids.

TaskTask

Determine the temperature coefficient of iron wire, copper wireand constantan wire in the range of room temperature to 95 °C.


▪ Electron conductivity▪ Ion conductivity



Cobra3 BASIC-UNIT, USB 12150-50 1


Cobra3 current probe 6 A 12126-00 1



Power supply 12V / 2A 12151-99 1






▪ Direct current source: Stabilised, regulated output directvoltage, continuously adjustable from 0...18 V; Adjustable cur-rent limit between 0...5 A

▪ LED display for constant current operationn▪ Permantely short-circuit proof &protected against exterior

voltages▪ Alternative voltage output:▪ Multitap transformer 2...15V, outputs galvanically separated

from mains grid▪ Full load capacity (5A), even if direct current is supplied sim-

ultaneously▪ Short-circuit protection through overcurrent circuit breaker▪ All output voltages available at 4 mm safety plug sockets.

13500-9313500-93

P3060111P3060111Charge transport in solids (with Cobra3)Charge transport in solids (with Cobra3)

Dependence of resistance versus temperature(iron wire).

Charge transport in solids (with Cobra4)Charge transport in solids (with Cobra4)

P3060160P3060160

6 Physical Chemistry6 Physical Chemistry6.6 Electro Chemistry


101

PrinciplePrinciple

A potential difference between two electrodes in a liquid causesthe flow of a current in the liquid. This current depends on thepotential drop across the liquid and its conductivity. The measure-ment of the conductivity of electrolyte solutions yields knowledgeabout charge transport in liquids. (Drying oven required!)

TasksTasks

1. Measure the change in conductivity caused by diluting a 0.1molar potassium chloride solution with distilled water.

2. Measure the conductivity of an aqueous potassium chloridesolution at different temperatures.

3. Explain the observed effects.


▪ Electrolyte solutions▪ Conductivity▪ Ionic migration






Hotplate Magnetic Stirrer, 5 ltr., 230 V 35730-93 1



Cobra4 Wireless-LinkCobra4 Wireless-Link


Interface module for the radio-based transmission of sensormeasuring values in conjunction with the Cobra4 Wireless Man-ager.

BenefitsBenefits

▪ All Cobra4 Sensor-Units can be quickly connected using a se-cure and reliable plug-in / lockable connection.

▪ All Cobra4 measuring sensors are easy to plug in and automat-ically detected.

▪ The radio network with the Cobra4 Wireless Manager is estab-lished automatically and is extremely stable, as it uses its ownradio protocol.

▪ Up to 99 Cobra4 Wireless-Links can be connected to one Co-bra4 Wireless Manager.

12601-0012601-00

P3060260P3060260 Charge transport in liquids (with Cobra4)Charge transport in liquids (with Cobra4)

Conductivity of an aqueous potassium chloridesolution at different temperatures.



102

PrinciplePrinciple

The movement of ions is responsible for current flow in solutionsof electrolytes. The migration of coloured ions can be easily ob-served by the migration of the colour front in an electric field.

TaskTask

Demonstrate the migration of the permanganate anion in an elec-tric field and measure the ionic velocity at five different concen-trations.


▪ Charge transport in liquids▪ Ion mobility▪ Conductivity


Power supply, 0...600 V DC 13672-93 1

Flat chamber for ionic migration 06605-00 1



Stopwatch, digital, 1/100 s 03071-01 1


Flat chamber for ionic migrationFlat chamber for ionic migration


For demonstrating the migration of coloured ions in an electrolyteand for the determination of the absolute mobility of ions.Transparent plastic plate with engraved groove; upper face of theplastic plate blackened, except the groove. At each end face of thegroove there is a nickel electrode with a 4 mm socket; thelongitudinal sides of the groove have a scale with 5 mm divisions.The upper face of the plastic plate has a water level for horizontaladjustment of the flat chamber. The process of ionic migration canbe especially well observed in projections using an overhead pro-jector.

06605-0006605-00

P3060301P3060301Ion migration velocityIon migration velocity

Location of colour interface versus time.



103

PrinciplePrinciple

Cations and anions contribute to charge transport in electrolyticprocesses in accordance with their different mobilities in an elec-tric field. Hittorf transport numbers characterise the fraction ofthe total charge transported by a particular ion during electrolysis.They enable the calculation of ionic conductivities, the values ofwhich are important in electrochemical practice. Transport num-bers are to be experimentally determined from the characteristicconcentration changes which take place at the cathode and theanode during electrolysis.

TaskTask

Determine the Hittorf transport numbers for hydronium and ni-trate ions from measurements resulting from the electrolysis of an0.1 molar nitric acid solution.


▪ Electrolysis▪ Faraday's laws of electrolysis▪ Charge transport▪ Ion mobility▪ Hittorf numbers



Multi-range meter w.overl.prot. 07021-01 1

Digital thermometer, NiCr-Ni, -50...+1300°C 07050-00 1

Double U-tube w.frits+cock, GL25 44451-00 1

Glass beaker, short, 5000 ml 36272-00 1








▪ Adjustable current limit between 0...5 A▪ LED display for constant current operationn▪ Permantely short-circuit proof &protected against exterior

voltages▪ Alternative voltage output: Multitap transformer 2...15V, out-

puts galvanically separated from mains grid

13500-9313500-93

P3060401P3060401 Transference numbersTransference numbers

Transport and electrode processes during elec-trolysis of diluted nitric acid.



104

PrinciplePrinciple

The electrical conductivity of an electrolytic solution is dependentnot only upon the type and concentration of the electrolytes, butalso other state values. Thus, an increase in conductivity is gener-ally observed with an increase in temperature. This is fundament-ally due to the exponential decrease of the solutions's viscosity. Inaqueous solutions a limit is reached at approximately 90°C. Abovethis temperature the conductivity again decreases.

TaskTask

Determine the temperature dependence of the conductivity of a10% sodium chloride solution from 20 °C to approximately 60 °C.


▪ Electrolytic resistance▪ Conductance▪ Specific and molar conductivity▪ Ion mobility▪ Equivalent conductance at infinite dilution▪ Kohlrausch's law▪ Ostwald's law of dilution▪ Transference numbers▪ Viscosity












BenefitBenefit

▪ Measure conductivity or temperature - multipurpose-sensor.

12632-0012632-00

Wilhelm OstwaldWilhelm Ostwald


P3060560P3060560Temperature dependence of conductivity (with Cobra4)Temperature dependence of conductivity (with Cobra4)

Diagram of the conductivity as a function of thetemperature.



105

PrinciplePrinciple

It is possible to differentiate between strong and weak electrolytesby measuring their electrical conductance. Strong electrolytes fol-low Kohlrausch's law, whereas weak electrolytes are described byOstwald's dilution law. The examination of the concentration de-pendence of the conductivity allows the molar conductivities ofinfinitely diluted electrolytes to be determined, and facilitates thecalculation of degree of dissociation and the dissociation con-stants of weak electrolytes.

TasksTasks

1. Determine the concentration dependence of the electricalconductivity of potassium chloride and acetic acid solutions.

2. Calculate the molar conductivity using data from themeasurements taken and determine the molar conductivityat infinite dilution by extrapolation.

3. Determine the dissociation constant of acetic acid.


▪ Kohlrausch's law▪ Equivalent conductivity▪ Temperature-dependence of conductivity▪ Ostwald's dilution law









Magnetic stirrer Mini / MSTMagnetic stirrer Mini / MST


Magnetic stirrer without heating for mixing smaller quantities.

BenefitsBenefits

▪ All housing parts are made of a sturdy, reinforced ABS plasticmaterial that is resistant to many chemicals

▪ Electronic speed control to protect the engine against uncon-trolled acceleration

▪ The speed is infinitely adjustable▪ Delivery includes a magnetic stirring bar


▪ Stirring capacity: max. 1l water▪ Speed: 100 .. 1000 rpm▪ Without heating▪ Diameter: 137 mm▪ Height: 51 mm; Weight: 0.6 kg

47334-9347334-93

P3060660P3060660 Conductivity of strong and weak electrolytes (with Cobra4)Conductivity of strong and weak electrolytes (with Cobra4)

Conductivity of a strong electrolyte as a functionof the concentration.



106

PrinciplePrinciple

The equivalent conductivity of strong electrolytes depends on theirconcentration. The quotient of the equivalent conductivity at acertain concentration and the equivalent conductivity at infinitedilution is called the conductivity coefficient, which is the result ofinterionic action.

TasksTasks

1. Measure the specific conductivities of various potassiumchloride and calcium chloride solutions and calculate theequivalent conductivities.

2. Determine the equivalent conductivities at infinite dilutionusing the Kohlrausch equation and calculate the conductivitycoefficients.


▪ Equivalent conductivity▪ Ion mobility▪ Conductivity▪ Interionic action







Conductivity temperature probe Pt1000Conductivity temperature probe Pt1000


Conductivity temperature probe Pt1000


▪ Cell constant k = 1.0 / cm▪ Minimum immersion depth: 10 mm

13701-0113701-01

P3060862P3060862Determination of the activity coefficient by a conductivityDetermination of the activity coefficient by a conductivitymeasurement (with Cobra4)measurement (with Cobra4)

Curves for potassium chloride and calciumchloride.



107

PrinciplePrinciple

The Nernst equation expresses how the electrical potential of anelectrode in contact with a solution of ions depends upon the con-centrations (more accurately, activities) of those ions. The equa-tion may be experimentally verified using an electrochemical cellformed from an inert indictator electrode coupled with a conveni-ent reference electrode. The potential of the indicator electrode,and hence the e.m.f. of the cell, is monitored as the ionic com-position of the electrolyte solution is changed.

TasksTasks

Using an Ag(S) I AgCl(S) l Cl- reference electrode, measure the po-tential of a platinum electrode in contant with solutions contain-ing known concentration of the iron(II) and iron(lII) complex ions[Fe(CN)6]4 - and [Fe(CN)6]3-.


▪ Electrode potentials and their concentration dependence▪ Redox electrodes▪ Electrochemical cells






Reference electrode, AgCl 18475-00 1



P3060962P3060962 Nernst equation (with Cobra4)Nernst equation (with Cobra4)

Verification of the Nernst equation for theFe(CN)6

4-, Fe(CN)63- Pt redox electrode.



108

PrinciplePrinciple

An electrochemical potential establishes itself at the interfacebetween two solutions of different ion concentrations. The mag-nitude of this is determined by the concentration ratio and thetransference numbers of the ions involved. This potentialdifference can be measured as a function of the concentration atsemi-permeable and ion-selective membranes.

TasksTasks

1. Measure the diffusion potential as a function of the concen-tration gradient at a cellophane membrane and at a cation-selective membrane.

2. Determine the transference numbers of the ions in HCl, NaCland KCl.


▪ Concentration cells with transport▪ Transference numbers▪ Semi-permeable membrane▪ Selectively permeable membrane▪ Nernst equation


Osmosis and electrochemistry chamber 35821-00 1




Gasket for GL25, 12mm hole, 10pcs 41243-03 1



Osmosis and electrochemistry chamberOsmosis and electrochemistry chamber


Osmosis and electrochemistry chamber for the demonstration andobservation of osmotic processes.

The chamber can be build up and cleaned without problems.Between two sealing rings arbitrary semipermeable membranescan be fixed. A measurable rise is achieved by the big boundarysurface of differently concentrated solutions very quickly in the ca-pillary tube. For the readout of the altitude a scale can be put onthe capillary tube.

35821-0035821-00

P3061101P3061101Determination of diffusion potentialsDetermination of diffusion potentials

Diffusion potential D jD for HCI as a function of

ln a2/a1 (o) and ln c2/c1 (x) (for cellophane).



109

PrinciplePrinciple

Thermodynamic data of the gross reaction in a galvanic cell can bedetermined by measuring the e.m.f. at different temperatures.

TaskTask

Determine the usable reaction equivalent work of the Daniell cellby measuring the dependence of the electromotive force on tem-perature.


▪ Electromotive force▪ Electrode reactions▪ Electrochemical potential▪ Nernst equation









P3061262P3061262 Temperature dependence of the electromotive force (withTemperature dependence of the electromotive force (withCobra4)Cobra4)

Electromotive force versus temperature.



110

PrinciplePrinciple

The course, reaction rate and equilibrium position of many chem-ical reactions are strongly influenced by the concentration or moreaccurately, the activity of hydrogen ions in solutions αH+. Rapidand accurate determinations of hydrogen ion activity are thus ofgreat importance. Since αH+ can vary over many orders of mag-nitude, it has proved convenient to introduce the pH scale (pHfrom the Latin "pondus hydrogenii" meaning "amount of hydro-gen"). The most important and common method used to determ-ine the pH value is to measure the potential of the electrode whichis sensitive to hydrogen ion activity.

In certain practical situations, however, a simpler and more directmethod of determining pH is required, and use is often made ofpH indicators.

TasksTasks

▪ Calibrate the following pH-sensitive electrodes in buffer solu-tions of known pH:

1. the glass electrode2. the antimony electrode3. the quinhydrone electrode

▪ Using these calibrated electrodes, measure the pH of an un-known solution. Compare and contrast the results obtainedwith the three pH-sensitive electrode.

▪ Use the glass electrode to determine the pH range in whichthe following indicators change colour:

1. methyl orange2. bromothymol blue3. phenolphthalein

▪ Compare the suitability of the three indicators for differenttypes of acid-base titrations.


▪ Potentiometric determination of pH▪ Glass electrode▪ pH indicators▪ Acid-base titrations




Antimony electrode 18477-01 1



Quinhydrone 100 g 31195-10 1


P3061562P3061562pH measurement (with Cobra4)pH measurement (with Cobra4)

Calibration curves for the antimony (o) andquinhydrone (x) electrode. The cell e.m.f. E ismeasured using a Ag(S)|AgCl(S)|Cl- (aq.) reference

electrode.



111

PrinciplePrinciple

If the oxidation and reduction steps of an electrode reaction arerapid (high exchange current densities) then the passage of chargeacross the electrode-solution interface will barely displace the re-action equilibrium. Such an electrode is said to be non-polarisablein the sense that its potential, for small currents, is stable andequal to the equilibrium electrode potential.

If, on the other hand, reaction equilibrium is established onlyslowly due to the kinetic inhibition of a step involved in the elec-trode reaction, then the electrode is said to be polarisable. To in-duce the reaction to proceed in a given direction the kinetic inh-hibition of the reaction must be overcome by applying a high over-potential.

Electrode polarisation and the presence of overpotentials are im-portant concepts in understanding electrode processes. They un-derlie the fact that galvanic cells always deliver current at lessthan the equilibrium e.m.f. and that an applied potential greaterthan the equilibrium e.m.f. is required in order to drive a reactionin an electrolytic cell.

Futhermore, a number of important electochemical devices (e.g.the lead-acid accumulator) and electroanalytical techniques (e.g.polarography) make use of the inhibition (high overpotential) ofcertain electrode reactions.

TasksTasks

1. Record the current-potential curve for the electrolysis of a1 M hydrochloric acid solution using graphite rod electrodesand determine the decomposition voltage.

2. Discuss the physical processes determining the form of thiscurve.

3. By replacing the graphite rod cathode with a series of differ-ent metal rod electrodes, compare the overpotentials for hy-drogen evolution at these metals.


▪ Electrode kinetics▪ Polarisation▪ Overpotential▪ Irreversible processes▪ The electrode-electrolyte interface▪ Voltammetry and current-potential curves▪ Relevance to electrolysis▪ Fuel cells▪ Corrosion▪ Polarography



Cobra3 BASIC-UNIT, USB 12150-50 1

Cobra3 current probe 6A 12126-00 1


Power supply 12V / 2A 12151-99 1

Nickel electrode, d = 8 mm 45205-00 1

Software Cobra3 Universal recorder 14504-61 1

Cobra4 ExperimentCobra4 Experiment

P3061811P3061811 Electrode kinetics: The hydrogen overpotential of metals (withElectrode kinetics: The hydrogen overpotential of metals (withCobra3)Cobra3)

Current-potential curve for the electrolysis ofHCI solution using graphite electrodes.

Electrode kinetics: The hydrogen overpotential of metalsElectrode kinetics: The hydrogen overpotential of metals(with Cobra4)(with Cobra4)

P3061860P3061860



112

PrinciplePrinciple

Faraday's laws of electrolysis describe the correlation between theamounts of substances transformed in the reactions at the elec-trodes and the charge applied (amount of electricity). Faraday'sconstant, which appears as a proportionality factor, can be de-termined experimentally from the dependence.

TasksTasks

Determine Faraday's constant from the dependence of thevolumes of hydrogen and oxygen envolved on the charge appliedin the hydrolysis of dilute sulphuric acid.


▪ Electrolysis coulometry▪ Charge▪ Faraday's laws▪ Avogadro's number▪ General equation of state for ideal gases



Electrolysis apparatus-Hofmann 44518-00 1



On/off switch 06034-01 1



Electrolysis apparatus-HofmannElectrolysis apparatus-Hofmann


Electrolysis apparatus-Hofmann.


▪ Electrolysis apparatus-Hofmann▪ 2 communicating glass tubes, l = 510 mm▪ Measuring range: 50 ml▪ Graduation: 0.2 ml

44518-0044518-00

P3062101P3062101Determination of Faraday's constantDetermination of Faraday's constant

Correlation between the transferred charge andthe evolved volumes of hydrogen and oxygen inthe electrolysis of diluted sulphuric acid (T =296.05 K and p =100.4 kPa).



113

PrinciplePrinciple

In a PEM electrolyser, the electrolyte consists of a proton-conduct-ing membrane and water (PEM = Proton-Exchange-Membrane).When an electric voltage is applied, hydrogen and oxygen areformed. The PEM fuel cell generates electrical energy from hydro-gen and oxygen. The electrical properties of the electrolyser andthe fuel cell are investigated by recording a current-voltage char-acteristic line. To determine the efficiency, the gases are stored insmall gasometers in order to be able to measure the quantities ofthe gases generated or consumed.

TasksTasks

1. Recording the characteristic line of the PEM electrolyser.2. Recording the characteristic line of the PEM fuel cell.3. Determination of the efficiency of the PEM electrolysis unit.4. Determination of the efficiency of the PEM fuel cell.


▪ Electrolysis▪ Electrode polarisation▪ Decomposition voltage▪ Galvanic elements▪ Faraday's law



PEM electrolyser 06748-00 1

Cobra4 Mobile-Link set, incl. rechargeablebatteries, SD memory card, USB cable andsoftware "measure" 12620-55 1

PEM fuel cell 06747-00 1

Cobra4 Sensor-Unit Weather: Humidity, Airpressure,Temperature, Light intensity,Altitude 12670-00 1

Gas bar 40466-00 1


PEM electrolyserPEM electrolyser


For the production of hydrogen and oxygen through electrolysis.


▪ Electrolyser and storage container for distilled water mountedon a stable baseplate.

▪ Without use of caustic lyes or acids.▪ Only distilled water is used for operating it.▪ Voltage input protected against polarity reversal.▪ Operating instructions with detailed description of experi-

ment.▪ Electrode surface: 16 cm2.▪ Output: 4 W.▪ Voltage required: 1.7...2 V.

06748-0006748-00

P2411100P2411100 Characteristic curve and efficiency of a PEM fuel cell and a PEMCharacteristic curve and efficiency of a PEM fuel cell and a PEMelectrolyserelectrolyser

Volume of the hydrogen generated by the PEMelectrolyser as a function of time at differentcurrent I.



114

PrinciplePrinciple

Electrogravimetry is an important analytical method for thequantitative determination or separation of species in solution.The technique involves the quantitative electrolytic deposition ofan element, usually a metal, on a suitable electrode in weighableform.

TaskTask

Perform an accurate electrogravimetric determination of theamount of copper in a given sample solution.


▪ Quantitative analysis▪ Gravimetry▪ Electrolysis▪ Overpotential▪ Electrode polarisation


Pt electrodes, electrogravimetry 45210-00 1







Digital multimeter 2010Digital multimeter 2010


3 ½ digit Steady performance digital-multimeter.

BenefitsBenefits

▪ Provides an overload protection and the functions of measur-ing like DCV, ACV, DCA, ACA, resistance, capacitance, frequency,diode, continuity test with buzzer and temperature.

▪ Ideal for the education- and service-fields.

Equipment and techical dataEquipment and techical data

▪ 3 ½-dgt. LCD display, 28 mm, with backlight▪ Manual range selection▪ Low battery indication▪ FE-Test▪ Peak-hold▪ Auto power off▪ Safety: IEC-1010-1; CAT II 1000 V

07128-0007128-00

P3062201P3062201Electrogravimetric determination of copperElectrogravimetric determination of copper

Electric circuit for electrolysis.



115

P1268360P1268360

PrinciplePrinciple

The electric potential of a metal in a salt solution of it is depend-ent on the concentration of the solution. A potential differencecan be measured between solutions of different concentrationswhen they are connected electrically conducting to one another.Two silver/silver nitrate half-cells to be are used to demonstratethis.

Voltage of a concentration cell (with Cobra4)Voltage of a concentration cell (with Cobra4)


P1282360P1282360

PrinciplePrinciple

The characteristics of a metal are determined to a great extentby how easily it can be oxidized. The listing of metals in the suc-cession of their oxidizability, i.e. according to their striving toform cations, is called the electrochemical series of metals. Whena metal is dipped into a solution which contains cations of thatmetal, a voltage is built up between the metal and the solutionin this half-cell. Connection together of two such half-cells ofdifferent metals so that they are electrically conducting enablesthe voltage difference between them to be measured. The elec-trochemical series of metals can be derived from measurementsof such voltage differences.

Electrochemical series of metals (with Cobra4)Electrochemical series of metals (with Cobra4)




116

PrinciplePrinciple

The boiling point of a solution is always higher than that of thepure solvent. The dependence of the temperature difference(elevated boiling point) on the concentration of the solute can bedetermined using a suitable apparatus.

TasksTasks

1. Measure the increase in the boiling point of water as afunction of the concentration of table salt, urea and hy-droquinone.

2. Investigate the relationship between the increase in boilingpoint and the number of pellets.

3. Determine the molar mass of the solute from the relationshipbetween the increase in boiling point and the concentration.


▪ Raoult's law; Henry's law; Ebullioscopic constants▪ Chemical potential; Gibbs-Helmholtz equation▪ Concentration ratio; Degree of dissociation



Heating mantle for roundbottom flask, 250ml, 230 V, with saftey switch 49542-93 1

Temp.probe, imm., PT100, -20...+300 °C,teflon 11759-04 1

Apparatus for elevation of boiling point 36820-00 1




Temperature meter digital, 4-2Temperature meter digital, 4-2


Modern, user-friendly designed instrument for measuring tem-perature and temperature differences at four different measuringpoints.

BenefitsBenefits

▪ Two demonstrative 4 digit LED display (+ sign), with 20 mmhigh digits for presentation of the values measured at the se-lected measuring points.

▪ RS 232 interface for simultaneous display and evaluation ofthe measured values from all four measuring points with acomputer.

13617-9313617-93

P3021001P3021001Boiling point elevationBoiling point elevation

Boiling point increase as a function of concen-tration of table salt in an aqueous solution.

6 Physical Chemistry6 Physical Chemistry6.7 Phase Equilibrium


117

PrinciplePrinciple

The freezing point of a solution is lower than that of the puresolvent. The depression of the freezing point can be determinedexperimentally using a suitable apparatus (cryoscopy). If the cryo-scopy constants of the solvent are known, the molecular mass ofthe substance dissolved can be determined.

TasksTasks

1. Determine the size of freezing point depression after dissolv-ing a strong electrolyte (NaCl) in water. By comparing the ex-perimental value with the theoretical one predicted for thisconcentration, determine the number of ions into which theelectrolyte dissociates.

2. Determine the molar mass of a non-electrolyte (hy-droquinone) from the value of freezing point depression.


▪ Raoult's law; Cryoscopic constant; Chemical potential▪ Gibbs-Helmholtz equation; Concentration ratio▪ Degree of dissociation; Van't Hoff factor




Apparatus for freezing point depression 36821-00 1



Gasket for GL25, 12 mm hole, 10 pcs. 41243-03 1


Crystal-lattice model iceCrystal-lattice model ice


High quality crystal-lattice model consisting of coloured woodenballs and metallic links; the model will be delivered completelyfixed.


▪ Scale to real crystals: 1 : 250 million▪ Diameter of the balls: approx. 20 mm

40022-0040022-00

P3021101P3021101 Freezing point depressionFreezing point depression

Cooling curve of water/table salt mixture.



118

PrinciplePrinciple

A boiling point diagram shows the boiling points of a binary mix-ture as a function of the vapour / liquid equilibrium of the mix-ture at constant pressure. The boiling points of various mixturesof methanol and chloroform are measured and the composition ofthe liquid phases are determined using refractometry and a calib-ration curve.

TasksTasks

1. Determine the refractive indices of the pure components andabout 10 different mixtures of known composition.

2. Plot the boiling point diagram of the binary mixtures ofmethanol and chloroform.


▪ Fundamentals of distillation▪ Equilibrium diagram▪ Chemical potential▪ Activity coefficient▪ Raoult's law


Abbe refractometer 35912-00 1





Column head, with stopcock, IGJ 19/26 35919-01 1


Abbe refractometerAbbe refractometer


Abbe refractometer for measuring the refraction index of liquidsand solids with light of 590 nm wavelength (sodium D line) anddetermining average dispersion nC-nF.The refractive index scale also includes an additional scale indic-ating sugar content from 0 - 95%. The prism and scales can beilluminated by daylight or by a separate lighting unit.

35912-0035912-00

P3030401P3030401Boiling point diagram of a binary mixtureBoiling point diagram of a binary mixture

Index of refraction as a function of substanceconcentration in methanol/chloroform mixtures.



119

PrinciplePrinciple

The temperature course during the melting and crystallization ofsodium thiosulphate is determined.

TaskTask

Investigate the temperature rise during crystallisation of sodiumthiosulfate.


▪ Melting▪ Crystallization▪ Sodium thiosulphate▪ Fusion enthalpy▪ Supercooled melt







Retort stand, 210 mm × 130 mm, h = 500mm 37692-00 1

Holder for Cobra4 with support rod 12680-00 1




As soon as a Cobra4 sensor is connected to a PC, irrespective ofwhether by Cobra4 Wireless or Cobra4 USB Link, the "measureCobra4" software opens completely automatically and shows theconnected sensors, the required measuring windows and the cur-rent measuring data.

14550-6114550-61

P1273460P1273460 Heat of fusion of sodium thiosulphate (with Cobra4)Heat of fusion of sodium thiosulphate (with Cobra4)

Measurement result, the temperature over timein the range from 20 °C to about 70 °C.



120

PrinciplePrinciple

In plotting the cooling curves of binary mixtures one determinesthe temperatures of melting and solidification of specimens withdiffering fractions (molar fractions) of the two components. Theseresults are entered in a temperature versus concentration dia-gram.

TasksTasks

1. Record the melting point diagram of a mixture of biphenyland naphthalene.

2. Determine the composition of the eutectic mixture and itsmelting point from the melting point diagram.


▪ Melt▪ Melting point▪ Melting point diagram▪ Binary system▪ Miscibility gap▪ Mixed crystal▪ Eutectic mixture▪ Gibbs' phase law




Cobra4 Sensor-Unit 2 x Temperature, NiCr-Ni 12641-00 1

Thermocouple NiCr-Ni, sheathed-50...1100°C 13615-01 1

Holder for Cobra4 with support rod 12680-00 1



P3031360P3031360Melting diagram of a binary mixture (with Cobra4 )Melting diagram of a binary mixture (with Cobra4 )

Cooling curve of a mixture of naphthalene andbiphenyl.



121

PrinciplePrinciple

Gases are condensing when they are cooled and at high pres-sure. In this experiment butane is condensed by cooling it to ca.-15 °C. In the second part of the experiment butane is condensedby compressing it.

TasksTasks

1. Condense butane by cooling it under its boiling point of -0.4°C.

2. Condense butane at high pressure.


▪ Condensation▪ Gas laws


Gasometer 1000 ml 40461-00 1

Gas liquefier 08173-00 1

Dewar vessel,500 ml 33006-00 1

Lab jack, 160 x 130 mm 02074-00 1

Butane burner, Labogaz 206 type 32178-00 1


Gas liquefierGas liquefier


Gas liquifier, for demonstrating isothermal condensation andevaporation due to changes in pressure and volume.


▪ Plastic-coated glass tube, piston with handle.▪ Length: 270 mm.▪ Diameter: 27 mm.

08173-0008173-00

P3011400P3011400 Condensation of gases through an increase of pressure andCondensation of gases through an increase of pressure andthrough coolingthrough cooling

Schematical setup of the experiment.



122

PrinciplePrinciple

Iodine, whose melting point is at 113.5 °C, evaporates clearly be-low this temperature. It passes from the solid state directly to thegaseous state. This process is known as sublimation.

When iodine vapour cools down, solid crystals form, again withouta liquid transitional phase. This process is known as resublima-tion.

TasksTasks

1. Show sublimation and resublimation of iodine.2. Investigate the solubility of iodine in oxygen-containing and

oxygen-free solvents.


▪ Sublimation▪ Resublimation▪ Solubility▪ Iodine


Round bottom flask, 250 ml, 2-neck, GL25/12, GL18/8 35843-15 1



Cyclohexane 1000 ml 31223-70 1

Condenser, reflux, with 2Gl conn. 35900-02 1

Closure caps,10, GL18 41220-03 1

Condenser, reflux, with 2 Gl connectionCondenser, reflux, with 2 Gl connection


Condenser, reflux, with 2 Gl connection.


▪ Jacket length: 190 mm▪ Diameter of the olives: 8 mm▪ Made of DURAN®

35900-0235900-02

P3031900P3031900Sublimation and solubility of iodineSublimation and solubility of iodine

Solubility of iodine in oxygenated and deoxy-genated solvents.



123

P3031251P3031251

PrinciplePrinciple

An elegant and simple apparatus for carrying out water vapourdistillations: the advantage of this arrangement is that it elimin-ates the need for a separate vapour generator, making it possibleto operate with a single heat source (other set-ups require two).The vapour is generated in the outer chamber and then passesthrough the inner chamber. Due to the structural arrangement,the inner chamber is heated directly by the vapour generated inthe outer chamber. This also eliminates the possibility of over-heating the substances being extracted.Parts of plants suitable for the extraction of essential oils includeorange peel and cloves, for example.

Steam distillationSteam distillation


P3031501P3031501

PrinciplePrinciple

The separation power of a rectification (fractionating) columncan be determined using an appropriate binary mixture whoseequilibrium composition is measured in the distillation flask andin the domed glass head of the distillation apparatus. The num-ber of theoretical trays can be numerically or graphically ob-tained from the measured values.

Rectification - the number of theoretical trays in a distillation columnRectification - the number of theoretical trays in a distillation column

For more details refer to pages 160, 177.For more details refer to pages 160, 177.

P3031640P3031640

PrinciplePrinciple

In countercurrent distillation (rectification) using a column, therising vapour can enter into interactions with the condensate. Inthis manner, a fractional distillation, i.e. a distillation in severalsteps for the separation of substances with similar boiling points,can be performed in a single apparatus. If bubble tray columnsare used condensate can be removed from the individual bubbletrays.

Fractional distillation with the bubble tray column (with Cobra3)Fractional distillation with the bubble tray column (with Cobra3)




124

PrinciplePrinciple

Electrons are accelerated in a tube filled with neon vapour. Theexcitation energy of neon is determined from the distancebetween the equidistant minima of the electron current in a vari-able opposing electric field.

TasksTasks

1. To record the counter current strength I in a Franck-Hertztube as a function of the anode voltage U.

2. To determine the excitation energy E from the positions ofthe current strength minima or maxima by difference form-ation.


▪ Energy quantum▪ Quantum leap▪ Electron collision▪ Excitation energy


Franck-Hertz control unit 09105-99 1

Franck-Hertz Ne-tube w. housing 09105-40 1

Connect.cord for Franck-H. Ne-tube 09105-50 1

Software Measure Franck-Hertz experiment 14522-61 1

Screened cable, BNC, l = 750 mm 07542-11 1

Data cable, plug/ socket, 9 pole 14602-00 1


James Franck (left) and Gustav Hertz (right)James Franck (left) and Gustav Hertz (right)


P2510315P2510315Franck-Hertz experiment with a Ne-tubeFranck-Hertz experiment with a Ne-tube

Example of a Franck-Hertz curve for Ne-gas.

Franck-Hertz experiment with a Hg-tubeFranck-Hertz experiment with a Hg-tube

P2510311P2510311

6 Physical Chemistry6 Physical Chemistry6.8 Atomic Structures and Properties


125

PrinciplePrinciple

The well-known spectral lines of He are used for calibrating thediffraction spectrometer. The wave-lengths of the spectral lines ofNa, Hg, Cd and Zn are determined using the spectrometer.

TasksTasks

1. Calibration of the spectrometer using the He spectrum andthe determination of the constant of the grating.

2. Determination of the spectrum of Na.3. Determination of the fine structure splitting.4. Determination of the most intense spectral lines of Hg, Cd

and Zn.


▪ Diffraction spectrometer; Spin▪ Angular momentum▪ Spin-orbital angular momentum interaction▪ Multiplicity; Energy level; Excitation energy▪ Selection rules; Doublets; Parahelium▪ Orthohelium, Exchange energy▪ Angular momentum; Singlet and triplet series▪ Selection rules; Forbidden transitions


Spectrometer/goniom. w. vernier 35635-02 1

Spectral lamp He, pico 9 base 08120-03 1

Power supply for spectral lamps 13662-97 1

Spectral lamp Na, pico 9 base 08120-07 1

Spectral lamp Hg 100, pico 9 base 08120-14 1

Spectral lamp Zn, pico 9 base 08120-11 1

Spectral lamp Cd, pico 9 base 08120-01 1

Spectrometer/goniometer with vernierSpectrometer/goniometer with vernier


Spectrometer/ goniometer with double vernier.


▪ With magnifying glasses▪ 60° glass prism▪ Illumination device and telescope

35635-0235635-02

P2510600P2510600 Fine structure: One and two electron spectraFine structure: One and two electron spectra

Spectrum of sodium.



126

PrinciplePrinciple

The spectral lines of hydrogen and mercury are examined bymeans of a diffraction grating. The known spectral lines of Hg areused to determine the grating constant. The wave lengths of thevisible lines of the Balmer series of H are measured.

TasksTasks

1. Determination of the diffraction grating constant by meansof the Hg spectrum.

2. Determination of the visible lines of the Balmer series in theH spectrum, of Rydberg's constant and of the energy levels.


▪ Diffraction image of a diffraction grating▪ Visible spectral range▪ Single electron atom▪ Atomic model according to Bohr▪ Lyman-, Paschen-, Brackett and Pfund Series▪ Energy level▪ Planck's constant▪ Binding energy



Object holder, 5x5 cm 08041-00 1

Spectrum tube, hydrogen 06665-00 1

Spectrum tube, mercury 06664-00 1

Diffraction grating, 600 lines/mm 08546-00 1


Insulating support 06020-00 2







▪ Selectable positive and negative polarity.▪ 3-figure LED display. Outputs short-circuit proof.▪ Special safety sockets.▪ Modern plastic housing, impact resistant, easy to service, light

stackable with retractable carrying handle and stand.▪ Internal resistance: approx. 5 MOhm.▪ Ripple: < 0.5%; Supply voltage: 230 V.▪ Short circuit current: max. 3 mA.▪ Housing dimensions (mm): 230 x 236 x 168.

13670-9313670-93

P2510700P2510700Balmer series/ determination of Rydberg's constantBalmer series/ determination of Rydberg's constant

Energy level diagram of the H atom.



127

PrinciplePrinciple

Electrons are accelerated in an electric field and enter a magneticfield at right angles to the direction of motion. The specific chargeof the electron is determined from the accelerating voltage, themagnetic field strength and the radius of the electron orbit.

TaskTask

Determination of the specific charge of the electron (e/m) from thepath of an electron beam in crossed electric and magnetic fieldsof variable strength.


▪ Cathode rays▪ Lorentz force▪ Electron charge▪ Electron in crossed fields▪ Electron mass


Narrow beam tube 06959-00 1

Helmholtz coils, one pair 06960-00 1

Power supply, 0...600 VDC 13672-93 1


e/m - Observation Chamber 06959-01 1


In Cooperation with:In Cooperation with:

National University of Science and TechnologyNational University of Science and Technology

"MISIS" in Moscow, Russia"MISIS" in Moscow, Russia

e/m - Observation chambere/m - Observation chamber


Observation Chamber for Covering the e/m experiment (helmholtzcoils and narrow beam tube).

06959-0106959-01

P2510200P2510200 Specific charge of the electron e/mSpecific charge of the electron e/m

Detail of experimental setup.



128

PrinciplePrinciple

The "Zeeman effect" is the splitting up of the spectral lines ofatoms within a magnetic field. The simplest is the splitting up ofone spectral line into three components called the "normal Zee-man effect".

In this experiment the normal Zeeman effect as well as the anom-alous Zeeman effect are studied using a cadmium spectral lamp asa specimen.

The cadmium lamp is submitted to different magnetic flux dens-ities and the splitting up of the cadmium lines (normal Zeemaneffect 643.8 nm, red light; anomalous Zeeman effect 508.6 nm,green light) is investigated using a Fabry-Perot interferometer.

The evaluation of the results leads to a fairly precise value forBohr's magneton.

TasksTasks

1. Using the Fabry-Perot interferometer and a selfmade tele-scope the splitting up of the central line into different linesis measured in wave numbers as a function of the magneticflux density.

2. From the results of point 1. a value for Bohr's magneton isevaluated.

3. The light emitted within the direction of the magnetic fieldis qualitatively investigated.


▪ Bohr's atomic model▪ Quantisation of energy levels▪ Electron spin▪ Bohr's magneton▪ Interference of electromagnetic waves▪ Fabry-Perot interferometer


Fabry-Perot interferometer 09050-02 1

Magnetic System, variable 06327-00 1

Cadmium lamp for Zeeman effect 09050-20 1


Sliding device, horizontal 08713-00 1

Optical profile-bench, l = 1000mm 08282-00 1

Polarising filter, on stem 08610-00 1

Pieter ZeemanPieter Zeeman


P2511006P2511006Zeeman effect with a variable magnetic systemZeeman effect with a variable magnetic system

Interference rings with the anomalous Zeemaneffect.



129

PrinciplePrinciple

A beam of potassium atoms generated in a hot furnace travelsalong a specific path in a magnetic two-wire field. Because of themagnetic moment of the potassium atoms, the nonhomogenity ofthe field applies a force at right angles to the direction of theirmotion. The potassium atoms are thereby deflected from theirpath. By measuring the density of the beam of particles in a planeof detection lying behind the magnetic field, it is possible to drawconclusions as to the magnitude and direction of the magneticmoment of the potassium atoms.

TasksTasks

1. Recording the distribution of the particle beam density inthe detection plane in the absence of the effective magneticfield.

2. Fitting a curve consisting of a straight line, a parabola, andanother straight line, to the experimentally determined spe-cial distribution of the particle beam density.

3. Determining the dependence of the particle beam density inthe detection plane with different values of the non-homo-genity of the effective magnetic field.

4. Investigating the positions of the maxima of the particlebeam density as a function of the non-homogeneity of themagnetic field.


▪ Magnetic moment; Bohr magneton; Directional quantisation▪ g-factor; Electron spin; Atomic beam▪ Maxwellian velocity distribution; Two-wire field


Stern-Gerlach apparatus 09054-88 1

High vacuum pump assembly,compact 09059-99 1

Step motor Stern-Gerlach appartus 09054-06 1

Electromagnet w/o pole shoes 06480-01 1

DC measuring amplifier 13620-93 1

Step motor unit 08087-99 1

Potassium ampoules, set of 6 09054-05 1

Otto SternOtto Stern


P2511111P2511111 Stern-Gerlach experiment with a step motor and interfaceStern-Gerlach experiment with a step motor and interface

Ionization current as a function of position (u)of detector with large excitation currents in themagnetic analyser.



130

PrinciplePrinciple

The basic principles concerning the phenomenon of nuclear mag-netic resonance (NMR) are demonstrated. Experiments are ex-ecuted with a MRT training device giving the opportunity to in-vestigate some small probes in the sample chamber. Device controlis done with the provided software. Investigations comprise thetuning of the system frequency to the Larmor frequency, the de-termination of the flip angle of the magnetisation vector, the ef-fects of the substance quantity, the influence of particular mag-netic field inhomogeneities, the measurement of a spin echo sig-nal and an averaging procedure to maximise the signal-to-noiseratio. The adjustment of all parameters in these experiments areinevitable to obtain an adequate MR image.

TasksTasks

1. Tuning of the system frequency to the Larmor frequency.2. Setting of the HF (High Frequency) pulse duration to determ-

ine the flip angle of the magnetisation vector.3. Effects of the substance quantity on the FID signal (Free In-

duction Decay) amplitude.4. Minimising magnetic field inhomogeneities via a superim-

posed magnetic field (shim).5. Retrieving a relaxated FID signal via a spin echo flipping nuc-

lear spins by 180°.6. Improving the signal-to-noise ratio (SNR) of the FID signal.


▪ Nuclear spins; Atomic nuclei with a magnetic moment▪ Precession of nuclear spins; Magnetisation▪ Resonance condition, MR frequency▪ MR flip angle▪ FID signal (Free Induction Decay); Spin echo▪ Relaxation times (T1: longitudinal magnetisation, T2: trans-

verse magnetisation); Signal-to-noise ratio


Compact magnetic resonance tomograph(MRT) 09500-99 1

Felix Bloch (left) and Edward Mills Purcell (right)Felix Bloch (left) and Edward Mills Purcell (right)


P5942100P5942100Basic principles in Nuclear Magnetic Resonance (NMR)Basic principles in Nuclear Magnetic Resonance (NMR)

Spin echo signal of an oil sample occuring 10 ms(echo time) after a 90° HF pulse (FID signal isshown). To generate the echo signal a 180° HFpulse has to be switched after half the echotime.



131

PrinciplePrinciple

The refractive indices of liquids, crown glass and flint glass are de-termined as a function of the wave length by refraction of lightthrough the prism at minimum deviation. The resolving power ofthe glass prisms is determined from the dispersion curve.

TasksTasks

1. To adjust the spectrometer-goniometer.2. To determine the refractive index of various liquids in a hol-

low prism.3. To determine the refractive index of various glass prisms.4. To determine the wavelengths of the mercury spectral lines.5. To demonstrate the relationship between refractive index

and wavelength (dispersion curve).6. To calculate the resolving power of the glass prisms from the

slope of the dispersion curves.7. Determination of the grating constant of a Rowland grating

based on the diffraction angle (up to the third order) of thehigh intensity spectral lines of mercury.

8. Determination of the angular dispersion of a grating.9. Determination of the resolving power required to separate

the different Hg-Lines. Comparison with theory.


▪ Maxwell relationship▪ Dispersion▪ Polarisability▪ Refractive index▪ Prism▪ Rowland grating▪ Spectrometer▪ Goniometer


Spectrometer/goniom. w. vernier 35635-02 1


Spectral lamp Hg 100, pico 9 base 08120-14 1

Hollow prism 08240-00 1

Lamp holder,pico 9,f.spectr.lamps 08119-00 1

Diffraction grating, 600 lines/mm 08546-00 1

Prism, 60 degrees, h.30 mm, crown 08231-00 1

Spectrometer/goniom. w. vernierSpectrometer/goniom. w. vernier


Spectrometer/ goniometer with double vernier.


▪ With magnifying glasses▪ 60° glass prism▪ Illumination device and telescope

35635-0235635-02

P2210300P2210300 Dispersion and resolving power of a prism and a gratingDispersion and resolving power of a prism and a gratingspectroscopespectroscope

Dispersion curves of various substances.



132

134134137137138138140140152152

Inorganic ChemistryInorganic Chemistry7.17.1 Chemistry of MetalsChemistry of Metals7.27.2 Coordination ChemistryCoordination Chemistry7.37.3 Organometallic ChemistryOrganometallic Chemistry7.47.4 Solid-state Chemistry and CristallographySolid-state Chemistry and Cristallography7.57.5 LiteratureLiterature

7 Inorganic Chemistry7 Inorganic Chemistry


133

PrinciplePrinciple

The experiments described here are highly suitable for demon-strating the different affinity of various metals in view of oxygen.The less noble a metal is the higher its affinity to oxygen and themore thermal energy is released during its oxidation. The technic-al importance of the thermite process for the welding of iron partsis that it is relatively easy to produce large amounts of liquid ironand, thereby, to fill wider weld grooves. This is why this processis mainly used for welding thick steel beams, rail tracks, and ma-chine parts.

TasksTasks

1. Reduction of copper oxide with iron.2. Reduction of iron oxide with aluminium (thermite process, alu-minothermics).


▪ Redox reaction; Thermite process▪ Metals; Welding of iron▪ Aluminothermics▪ Iron; Aluminium



Iron powder xtra pure 1000 g 30068-70 1

Magnet, d 10mm, l = 200mm 06311-00 1


Ignition sticks f. thermite, 50 pcs. 31921-05 1


P3110600P3110600 Redox reactions between metals and metal oxides (thermiteRedox reactions between metals and metal oxides (thermiteprocess)process)

Experimental setup.

7 Inorganic Chemistry7 Inorganic Chemistry7.1 Chemistry of Metals


134

PrinciplePrinciple

The electrolysis of molten sodium chloride to obtain chlorine andsodium, which can be further processed to produce sodium hy-droxide, is an important industrial-scale process. The experimentdepicted here can be used for a simple demonstration of the im-portant steps in this process. Due to the high melting point ofsodium chloride, however, lower-melting lead chloride is used asthe raw material in the model experiment.

TaskTask

Demonstration the electrolysis of molten sodium chloride to ob-tain chlorine and sodium.


▪ Electrolysis▪ Melt▪ Chlorine▪ Starch-iodine solution


Multimeter ADM2, demo., analoque 13820-00 1



Shelf with hanging device 45505-00 1

Wash tube with fritted disc 36699-00 1

Lead-II chloride 500 g 31117-50 1



Crystal-lattice model fluoriteCrystal-lattice model fluorite


High quality crystal-lattice model consisting of coloured woodenballs and metallic links; the model will be delivered completelyfixed.

40018-0040018-00

P1310500P1310500Molten-salt electrolysisMolten-salt electrolysis

Oxidation/reduction process during the experi-ment.

Oxidation of metalsOxidation of metals

P1025200P1025200

Effects of acids on metalsEffects of acids on metals

P3100100P3100100



135

PrinciplePrinciple

Lead oxide is reduced to lead; in the process the carbon is oxidisedto carbon dioxide. ln this experimental set-up and also in theblast furnace process, the reducing agent proper is not carbon, butrather the carbon monoxide generated due to the oxygen deficit.

TaskTask

Demonstrate the reduction of lead oxide.


▪ Lead▪ Carbon monoxide▪ Reduction▪ Oxidation▪ Redox reaction


Support base variable 02001-00 1

Lead-II oxide -litharge- 500 g 31121-50 1

Bunsen burner DIN, natural gas 32165-05 1


Ring with boss head, i. d. = 10 cm 37701-01 1

Support rod, stainless steel, l = 600 mm, d =10 mm 02037-00 1

Safety gas tubing, DVGW, sold by metre 39281-10 1


P3100400P3100400 Reduction of lead oxideReduction of lead oxide

The blast furnance with which iron can be ob-tained from iron oxide.

Reduction of silver oxideReduction of silver oxide

P1026800P1026800

Reduction of copper oxideReduction of copper oxide

P1026900P1026900



136

PrinciplePrinciple

Many metals, in particular transition elements, can form com-plexes with charged or neutral ligands. Complex formation reac-tions are equilibrium reactions. The stability of these complexes isdescribed by the complex formation constant.

TasksTasks

Determine the number of ligands of the silver amine complex witha precipitation titration from a silver salt solution.


▪ Complex formation▪ Chemical equilibrium▪ Equilibrium constant





Burette, lateral stopcock, Schellbach, 25 ml,graduations0,05 ml 36506-01 1



Molecular orbital models, organicsMolecular orbital models, organics


The kit includes all the parts to build up 4 molecular orbital mod-els of the following organic compounds: benzene, ethane, ethyl-ene and acetylene.

BenefitsBenefits

The models show bonding s- and p- orbitals. The concept of hy-bridisation and delocalisation can be demonstrated so well.

39837-0039837-00

P3031001P3031001Complex formation equilibrium / complex formation constantComplex formation equilibrium / complex formation constant

Determination of the number of ligands boundin the complex.

7 Inorganic Chemistry7 Inorganic Chemistry7.2 Coordination Chemistry


137

PrinciplePrinciple

Haloalkanes react with magnesium to the so-called Grignard re-agents in accordance with the general formula RMgX. With X =bromide or iodide, the reaction works best. Chlorides are usuallymore inert and require higher temperatures and longer reactiontimes for the conversion. The compounds that were discovered byVictor Grignard probably exist as dimeric structures.

TaskTask

Investigate the reaction of n-propyl bromide with magnesiumturnings in tetrahydrofuran.


▪ n-propyl bromide▪ Magnesium▪ Haloalkanes▪ Grignard reagent▪ Organometallic compounds


Gasometer 1000 ml 40461-00 1




Separating funnel, 50 ml, GL18 35853-15 1

Funnel f. gas generator, 50 ml, GL18 35854-15 1

Set of Precision Balance Sartorius CPA 623Sand measure software, 230 V 49224-88 1 François Auguste Victor GrignardFrançois Auguste Victor Grignard


P3101000P3101000 Haloalkanes: Grignard reagentHaloalkanes: Grignard reagent

Set-up to determine the molar mass of the gasthat is produced during the reaction.

7 Inorganic Chemistry7 Inorganic Chemistry7.3 Organometallic Chemistry


138

PrinciplePrinciple

Unlike the other alkali-organyls, lithium organyls - with the ex-ception of methyllithium - show a stronger covalent behaviour.They dissolve rather well in organic solvents, such as diethyl ether,tetrahydrofuran, and alkanes, and they are relatively stable inthese solvents.Wurtz synthesis was developed in 1854 for the preparation ofhigher alkanes based on haloalkanes. Alkyl iodides react the easi-est. The reaction can be controlled best with lithium, since theother alkali metals react much more violently. Wurtz synthesis isoften a side reaction that occurs during organometallic conver-sions.

TaskTask

Investigate the reaction of ethyl iodide with lithium and the fol-lowing reaction of ethyllithium with ethyl iodide.


▪ Alkali-organyls; Lithium organyls▪ Wurtz synthesis; Organometallic compounds


Gasometer 1000 ml 40461-00 1



Gasket for GL25, 8 mm hole, 10 pcs. 41242-03 1


Round bottom flask, 100 ml, GL25/12, GL18/8 35842-15 1


Gasometer 1000 mlGasometer 1000 ml


Gasometer.


▪ Content 1000 ml▪ Adjustable outer scale▪ Readability 10 ml

40461-0040461-00

P3101100P3101100Haloalkanes: Wurtz reaction - lithium organylsHaloalkanes: Wurtz reaction - lithium organyls

Reaction of lithium with ethyl iodide and thefollowing Wurtz reaction of ethyl lithium withethyl iodide.

7 Inorganic Chemistry7 Inorganic Chemistry7.3 Organometallic Chemistry


139

7 Inorganic Chemistry7 Inorganic Chemistry7.4 Solid-state Chemistry and Cristallography


140



141



142

PrinciplePrinciple

The spectra of the X-rays that are reflected with various differentorientations by NaCl monocrystals are analysed. The associated in-terplanar spacings are determined based on the Bragg angles ofthe characteristic lines.

TasksTasks

1. Determine the intensity of the X-rays that are reflected bythe NaCl monocrystals with the orientations [100], [110], and[111] as a function of the Bragg angle.

2. Assign the reflections to the corresponding lattice planes thatare given by way of their respective Miller indices.

3. Determine the lattice constant and calculate the interplanarspacing.

4. Determine the mass of a cell and the number of atoms in thecell.


▪ Characteristic X-radiation▪ Energy levels▪ Crystal structures▪ Reciprocal lattices▪ Miller indices▪ Atomic form factor▪ Structure factor▪ Bragg scattering




XR 4.0 X-ray Plug-in Cu tube 09057-50 1

XR 4.0 X-ray NaCl-monocrystals, set of 3 09058-01 1

XR 4.0 Software measure X-ray 14414-61 1

Geiger-Mueller Counter tube, type B 09005-00 1


Sir William Henry Bragg (left) andSir William Henry Bragg (left) andSir William Lawrence Bragg (right)Sir William Lawrence Bragg (right)


P2541301P2541301Examination of the structure of NaCl monocrystals with differentExamination of the structure of NaCl monocrystals with differentorientationsorientations

Intensity of the X-ray spectrum of copper as afunction of the glancing angle theta: NaClmonocrystals with [111] crystal orientation asBragg analyser.


09110-8809110-88

XRS 4.0 X-ray structural analysis upgrade setXRS 4.0 X-ray structural analysis upgrade set

09140-8809140-88



143

PrinciplePrinciple

When polycrystalline samples are irradiated with X-rays a char-acteristic diffraction pattern results. These Debye-Scherrer reflec-tions are photographed and then evaluated.

TasksTasks

1. Debye-Scherrer photographs are to be taken of powderedsamples of sodium chloride and caesium chloride.

2. The Debye-Scherrer rings are to be evaluated and assigned tothe corresponding lattice planes.

3. The lattice constants of the sample materials are to be de-termined.

4. The number of atoms in the unit cells of each sample are tobe determined.


▪ Crystal lattices; Crystal systems▪ Reciprocal lattice; Miller indices▪ Structure amplitude▪ Atomic form factor▪ Bragg scattering



XR 4.0 X-ray Plug-in Mo tube 09057-60 1

XR 4.0 X-ray film holder 09057-08 1

XR 4.0 X-ray optical bench 09057-18 1

XR 4.0 X-ray films, wet chemical, 100 pieces,100 × 100 mm 09058-23 1

XR 4.0 X-ray Diaphragm tube d = 1 mm 09057-01 1

Slide mount for optical bench, h = 30 mm 08286-01 1



P2541401P2541401 X-ray investigation of cubic crystal structures / Debye- ScherrerX-ray investigation of cubic crystal structures / Debye- Scherrerpowder methodpowder method

Debye-Scherrer pattern of a powdered sample ofNaCl. Thickness of the sample: 0.4 mm. Exposuretime: 2.5 h. Mo X-ray tube: Ua = 35 kV; Ia = 1mA

X-ray investigation of hexagonal crystal structures /X-ray investigation of hexagonal crystal structures /Debye-Scherrer powder methodDebye-Scherrer powder method

P2541501P2541501


09110-8809110-88

XRS 4.0 X-ray structural analysis upgrade setXRS 4.0 X-ray structural analysis upgrade set

09140-8809140-88



144

PrinciplePrinciple

Laue diagrams are produced when monocrystals are irradiatedwith polychromatic X-rays. This method is primarily used for thedetermination of crystal symmetries and the orientation of crys-tals. When a LiF monocrystal is irradiated with polychromatic X-rays, a characteristic diffraction pattern results. This pattern isphotographed with the digital X-ray sensor XRIS.

TasksTasks

1. The Laue diffraction of an LiF mono-crystal is to be recordedon a film.

2. The Miller indices of the corresponding crystal surfaces are tobe assigned to the Laue reflections


▪ Crystal lattices; Crystal systems; Crystal classes▪ Bravais lattice; Reciprocal lattice; Miller indices▪ Structure amplitude; Atomic form factor; The Bragg equation


XR 4.0 X-ray Direct Digital Image Sensor (XRIS)with USB cable 09057-40 1


XR 4.0 Software measure CT 14421-61 1


XR 4.0 X-ray Lithium fluoride crystal,mounted 09056-05 1

XR 4.0 X-ray optical bench 09057-18 1

XR 4.0 X-ray Crystal holder for Laue-pattern 09058-11 1

Related X-ray ExperimentRelated X-ray Experiment


Max von LaueMax von Laue


P2541602P2541602X-ray investigation of crystal structures / Laue method withX-ray investigation of crystal structures / Laue method withdigital X-ray image sensor (XRIS)digital X-ray image sensor (XRIS)

Laue pattern of the LiF (100) crystal.

X-ray investigation of crystal structures / Laue methodX-ray investigation of crystal structures / Laue method

P2541601P2541601


09110-8809110-88

XRCT 4.0 X-ray Computed Tomography upgrade setXRCT 4.0 X-ray Computed Tomography upgrade set

09180-8809180-88



145

PrinciplePrinciple

Polycrystalline powder samples, which crystallize in the three cubicBravais types, simple, face-centered and body-centered, are irra-diated with the radiation from a Roentgen tube with a copperanode. A swivelling Geiger-Mueller counter tube detects the ra-diation that is constructively reflected from the various latticeplanes of the crystallites. The Bragg diagrams are automatically re-corded. Their evaluation gives the assignment of the Bragg lines tothe individual lattice planes, their spacings as well as the latticeconstants of the samples, and so also the corresponding Bravaislattice type.

TasksTasks

1. Record the intensity of the Cu X-rays back scattered by thefour cubic crystal powder samples with various Bravais latticetypes as a function of the scattering angle.

2. Calculate the lattice plane spacings appropriate to the angu-lar positions of the individual Bragg lines.

3. Assign the Bragg reflections to the respective lattice planes.Determine the lattice constants of the samples and theirBravais lattice types.

4. Determine the number of atoms in the unit cell.


▪ Crystal lattices▪ Crystal systems▪ Bravais-lattice▪ Reciprocal lattice▪ Miller indices▪ Structure factor▪ Atomic scattering factor▪ Bragg scattering▪ Characteristic X-rays▪ Monochromatisation of X-rays▪ Bragg-Brentano Geometry






Geiger-Mueller Counter tube, type B 09005-00 1


Molybdenum, Powder, 99,7%, 100 g 31767-10 1


P2542101P2542101 Debye-Scherrer diffraction patterns of powder samples withDebye-Scherrer diffraction patterns of powder samples withthree cubic Bravais lattices (Bragg-Brentano-geometry)three cubic Bravais lattices (Bragg-Brentano-geometry)

Bragg-Cu-Kα and Cu-Kβ-lines of Mo.

Debye-Scherrer diffractions pattern of powder samplesDebye-Scherrer diffractions pattern of powder sampleswith a diamond structure (according to Bragg-Brentano)with a diamond structure (according to Bragg-Brentano)

P2542201P2542201

Debye-Scherrer diffraction patterns of powder samplesDebye-Scherrer diffraction patterns of powder sampleswith a hexagonal lattice structurewith a hexagonal lattice structure

P2542301P2542301

Debye-Scherrer diffraction patterns of powder samplesDebye-Scherrer diffraction patterns of powder sampleswith a tetragonal lattice structurewith a tetragonal lattice structure

P2542401P2542401

Debye-Scherrer diffraction patterns with a cubic powderDebye-Scherrer diffraction patterns with a cubic powdersamplesample

P2542501P2542501



146

PrinciplePrinciple

Polycrystalline powder samples, which crystallize in the three cubicBravais types, simple, face-centered and body-centered, are irra-diated with the radiation from a Roentgen tube with a copperanode. A swivelling Geiger-Mueller counter tube detects the ra-diation that is constructively reflected from the various latticeplanes of the crystallites. The Bragg diagrams are automatically re-corded. Their evaluation gives the assignment of the Bragg lines tothe individual lattice planes, their spacings as well as the latticeconstants of the samples, and so also the corresponding Bravaislattice type.

TasksTasks

1. Record the intensity of the Cu X-rays back scattered by thefour cubic crystal powder samples with various Bravais latticetypes as a function of the scattering angle.

2. Calculate the lattice plane spacings appropriate to the angu-lar positions of the individual Bragg lines.

3. Assign the Bragg reflections to the respective lattice planes.Determine the lattice constants of the samples and theirBravais lattice types.

4. Determine the number of atoms in the unit cell.


▪ Crystal lattices; Crystal systems; Bravais-lattice▪ Reciprocal lattice; Miller indices; Structure factor▪ Atomic scattering factor; Bragg scattering▪ Characteristic X-rays; Monochromatization of X-rays▪ Bragg Brentano geometry






Geiger-Mueller counter tube, type B 09005-00 1


Germanium, Powder, 99%, 10 g 31768-03 1

P2542201P2542201Debye-Scherrer diffractions pattern of powder samples with aDebye-Scherrer diffractions pattern of powder samples with adiamond structure (according to Bragg-Brentano)diamond structure (according to Bragg-Brentano)

Bragg-Cu-Kα and Cu-Kβ lines of germanium

powder



147

PrinciplePrinciple

Approaching a very sharp metal tip to an electrically conductivesample by applying a electrical field leads to a current between tipand sample without any mechanical contact. This so-called tun-neling current is used to investigate the electronic topography onthe sub nanometer scale of a fresh prepared graphite (HOPG) sur-face. By scanning the tip line-by-line across the surface graphiteatoms and the hexagonal structure are imaged.

TasksTasks

1. Prepare a Pt-Ir tip and the graphite (HOPG) sample and ap-proach the tip to the sample.

2. Investigate the topography of clean terraces and the stepheight between neighboring terraces in constant-currentmode.

3. Image the arrangement of graphite atoms on a clean terraceby optimize tunneling and scanning parameters. Interpretthe structure by analyzing angles and distances betweenatoms and atomic rows and by using the 2D and 3D graphitemodel.

4. Measure and compare images in the constant-height andconstant-current mode.


▪ Tunneling effect; Hexagonal Structures▪ Scanning Tunneling Microscopy (STM)▪ Imaging on the sub nanometer scale▪ Piezo-electric devices; Local Density Of States (LDOS)▪ Constant-Height-Mode; Constant-Current-Mode


Compact-Scanning Tunneling Microscope(STM) 09600-99 1

Crystal lattice kit: graphite 39840-00 1

Graphite model, 2D 09620-00 1

Heinrich Rohrer (left) and Gerd Binnig (right)Heinrich Rohrer (left) and Gerd Binnig (right)


P2532000P2532000 Atomic Resolution of the graphite surface by STM (ScanningAtomic Resolution of the graphite surface by STM (ScanningTunneling Microscope)Tunneling Microscope)

Atomic resolved image of the graphite surface(5nm x 5nm).



148

Compact-Scanning Tunneling MicroscopeCompact-Scanning Tunneling Microscope(STM)(STM)


Easy to use scanning tunneling microscope to image conductingsurfaces and to investigate effects and characteristics on atomicand molecular scale. A variety of experiments in the fields ofMaterial Sciences, Solid State Physics/Chemistry, Nanotechnologyand Quantum Mechanics can be performed. For example: micro-and nano morphology of surfaces, nano structures, imaging ofatoms and molecules, conductivity, tunneling effect, charge dens-ity waves, single molecule contacts, and nanostructuring by selforganisation (self assembled monolayers).

BenefitsBenefits

▪ Out-of-the-box-device incl. all necessary accessories for aprompt entry into the world of atoms and molecules.

▪ Portable and compact: transportable, easy to install with asmall footprint.

▪ Single device for more stable measurements.▪ Quick atomic resolution on a normal table. No need for ex-

pensive vibration isolation.

▪ Easy to use: Ideal for nanotechnology education, preparingstudents for their work on high-level research devices, andoutreach.

▪ Accessible sample stage and scanning tip: Quick exchange oftip and sample.

▪ Low operating voltage: Safe for all users.


▪ Scan head with integrated control-unit on vibration-isolatedexperimentation board:▪ Maximum scan range (XY) 500 nm x 500 nm▪ Maximum Z-range 200 nm▪ Resolution in XY better than 8 pm▪ Resolution in Z better than 4 pm▪ Current 0.1-100 nA in 25 pA steps▪ Tip voltage +/-10 V in 5 mV steps▪ Dimensions 21 cm x 21 cm x 10 cm▪ Constant-Current Mode▪ Constant-Height Mode▪ Current-Voltage Spectroscopy▪ Current-Distant Spectroscopy▪ Control-Unit with USB socket, 16-Bit

▪ DA converter for all three dimensions, up to 7 measure-ment channels, and maximum scanning speed of 60 ms/line

▪ Scan head cover with magnif. lense: 10x▪ Toolset for preparing and mounting tunneling tips: side-cut-

ter, tong and tweezers▪ Pt-Ir wire for tunneling tips: length 30 cm, diameter 0.25 mm▪ Sample kit: Graphite (HOPG), Gold(111) films, and 4 spare

sample supports▪ Power supply (100-240 V, 50/60 Hz)▪ USB cable: length 3 m; Aluminium case (44 cm x 32 cm x 14

cm)▪ Software for measuring, analysing and visualisation (one, two,

and three dimensions)▪ Handbook incl. short description of starting experiments with

HOPG and gold films; Quick Installation Guide; Weight (incl.case) 6.7 kg


▪ Computer with Windows 2000/XP/Vista/7, USB interface,256MB RAM, 1024x758 graphics card, 16-bit colour resolutionor better

▪ other samples▪ electrical conductive adhesive for mounting own samples▪ ethanol and cloth for cleaning

09600-9909600-99

Set samples nanomorphology, for CompactSet samples nanomorphology, for CompactScanning Tunneling Microscope (STM)Scanning Tunneling Microscope (STM)

09613-0009613-00

Left: Charge density waves onTaSLeft: Charge density waves onTaS22, 6nm, 6nm

Right: Gold film, 560nmRight: Gold film, 560nm

Left:Left: 2D-2D- melecularmelecular crystalcrystal (octadecanol)(octadecanol) onon graphitegraphite (HOPG),(HOPG),13nm13nm

Right: Graphite (HOPG), atomic resolution, 2nmRight: Graphite (HOPG), atomic resolution, 2nm



149

PrinciplePrinciple

Approaching a sharp silicon tip mounted on a cantilever to asample surface leads to an atomic scale interaction. The result is abend of the cantilever which is detected by a laser. In static modethe resulting deflection is used to investigate the topography ofthe sample surface line-by-line using a feedback loop. In dynamicmode the cantilever is oscillated at fixed frequency resulting in adamped amplitude near the surface. The measurement paramet-ers (setpoint, feedback gain,…) play a crucial role for image qual-ity. The dependence on the imaging quality is investigated for dif-ferent nano structured samples.

TasksTasks

1. Set-up the microscope and start up the software. Mount acantilever (with tip) and approach the tip towards a sample.

2. Investigate the influence of the scanning parameters on theimaging quality and performance, e.g. PID gain, setpoint(force), vibrational amplitude, and scanning speed. Use bothstatic and dynamic force mode.

3. Image 7 different samples (microstructures, carbon nanotubes, skin cross-section, bacteria, CD stamper, chip struc-ture, glass beads) by optimizing the parameters respectively.


▪ Atomic Force Microscopy (AFM)▪ Lennard-Jones potential▪ Imaging of nano structures▪ Static Force Mode; Dynamic Force Mode▪ Feedback Loop; Force▪ Vibrational Amplitude


Compact-Atomic Force Microscope (AFM) 09700-99 1


P2538000P2538000 Basic methods in imaging of micro and nanostructures withBasic methods in imaging of micro and nanostructures withatomic force microscopy (AFM)atomic force microscopy (AFM)

Topography of Microstructure (50 micrometer),CD Stamper (20 micrometer), Skin Cross-Section(60 micrometer), and SCA Chip Structure (40 mi-crometer) FLTR.

Imaging of biological and medical micro andImaging of biological and medical micro andnanostructure with atomic force microscopy (AFM)nanostructure with atomic force microscopy (AFM)

P2538400P2538400



150

Compact-Atomic Force Microscope (AFM)Compact-Atomic Force Microscope (AFM)


Compact and easy to use atomic force microscope to visualize andimage structures on the micro and nano meter scale. Developedfor educational purposes in practical lab course and pre-researchlabs in physics, chemistry, life sciences and material sciences. Alsosuitable to determine material characteristics (e.g. stiffness, mag-netization, charging, material and phase contrast) and for manip-ulation (e.g. lithography).

BenefitsBenefits

▪ Out-of–the-box device with integrated damping plate andcontrol unit underneath

▪ Complete set, incl. Sample Set, Cantilever, Tools and Consum-ables

▪ Tip Scanner AFM for standard cantilever▪ Easy and safe cantilever exchange and use: Flip mechanism

with automatic laser switch off, no laser alignement, mech-anical stopper for longer lifetime of cantilevers

▪ Digital top view camera for easy positioning and side view lensfor easy and fast approach

▪ Portable and compact: Transportable, easy to install with asmall footprint

▪ Easy to use: Ideal for nanotechnology education, preparingstudents for their work on high-level research devices, andoutreach

Equipment and technical DataEquipment and technical Data

▪ Scan head with integrated control-unit on vibration-isolatedexperimentation board: 21 cm x 21 cm x 18 cm, USB 2.0 in-terface, 16 bit DA converter (XYZ), 16 bit AD converter ( 7 chan-nels)

▪ Max scanning speed 60 ms/line, up to 2048x2048 data points▪ Scan type (tip scanner): Linear low voltage electro magnetic▪ Scan Range: 70 micro meter (1.1 nm resolution)▪ Z-range: 14 micro meter (1.1 nm resolution); Z noise level

(RMS): 0.6 / 0.5 nm (static / dynamic); Automatic approach:vertical, range 4.5 mm

▪ Sample: max. 13 mm in diameter, horizontal mount, LED illu-mination, Micrometer translation stage xy: min. +/- 5 mm

▪ Cantilever Aligment: automatic adjustment, alignmentgrooves from various suppliers; Camera system for top view:USB digital color, 3.1 M pixels

▪ Modes of operation: Static Force, Dynamic Force, ForceDistance Spectroscopy, Amplitude Distance Spectroscopy

▪ Other modes (MFM, AFM, Phase contrast, lithography and ad-vanced spectroscopy modes)

▪ Available with upgrade options material and spectroscopy andmanipulation

▪ User expandability (scripting) available (upgrade option); Setof 10 Cantilever, 6 samples, Toolset

▪ Software for measuring, manipulation, analysing and visualiz-ation, Handbook and Quick Installation Guide


▪ Material upgrade (Art. 09701-00): Additional Operating Modes(Phase Contrast, EFM, MFM, Force

▪ Modulation, Spreading Resistance), set of samples and canti-levers

▪ Spectroscopy and Manipulation upgrade (Art. 09702-00): Ad-ditional Operating Modes (Advanced Spectroscopy, Lithography(scratching, oxidation), Manipulation (oxidation, cutting andmoving/pushing of nanoparticles)), User expandability (Visualbasic, LabView, etc.), set of cantilevers and samples

▪ Side View Camera System (available 2013), other samples

09700-9909700-99

StaphylococcusStaphylococcus Bacteria,Bacteria, 1010 μmm andand SkinSkin Cross-Section,Cross-Section, 6060μmm

CD Stamper, 20 CD Stamper, 20 μm and Aluminum foil, 60 m and Aluminum foil, 60 μmm

PS/PMMA films: Topography and Phase Contrast, 3 PS/PMMA films: Topography and Phase Contrast, 3 μmm



151

Handbook Physics X-Ray ExperimentsHandbook Physics X-Ray Experiments


Experiments with X-rays and their use in physics, chemistry, bio-logy, medicine, material science, and geology.


Comprehensive collection of reference experiments concerning thefundamental principles and use of X-rays in physics, chemistry,biology, medicine, material science, and geology with the XR 4.0X-ray unit platform as a pool of ideas concerning the potentialareas of application in demonstration and laboratory experi-ments. A clear matrix simplifies the orientation in terms of sci-entific fields and topics.

TopicsTopics

▪ Characteristic X-radiation / atomic structure / quantum physicsand chemistry

▪ X-ray absorption▪ Compton scattering▪ Dosimetry▪ Crystal structures/structural analysis with X-rays/Debye-Scher-

rer experiments (counting tube goniometer)▪ Transirradiation experiments/non-destructive testing

FeaturesFeatures

▪ Experiment descriptions with clearly structured learning ob-jectives, fundamental principles, photo of the setup, equip-ment list, tasks, illustrated instructions concerning the setupand procedure, theory and evaluation with example resultsplus important notes concerning the operation and safety ofthe equipment. This simplifies the orientation and executionas well as the selection of the experiment parts for person-alised laboratory experiments. The information provided is socomprehensive that no other background information is re-quired.

▪ For every experiment, the software package "XRM 4.0 measureX-ray" includes presettings for the easy and direct execution of

the experiment at the push of a button as well as numerousexample measurements.

▪ Experiment matrix for quick orientation.▪ Operating instructions concerning the components of the XR

4.0 platform including detailed information.▪ DIN A4 format, spiral-bound, colour print.


Counter tube characteristicsP2540010P2540010

Radiographic examination of objectsP2540020P2540020

Qualitative examination of the absorption of X-raysP2540030P2540030

Ionising effect of X-radiationP2540040P2540040

Characteristic X-rays of copperP2540101P2540101

Characteristic X-rays of ironP2540301P2540301

The intensity of characteristic X-rays as a function of the anodecurrent and anode voltageP2540401P2540401

Monochromatisation of molybdenum X-raysP2540501P2540501

Monochromatisation of copper X-raysP2540601P2540601

K alpha double splitting of molybdenum X-rays/ fine structureP2540701P2540701

K alpha doublet splitting of iron X-rays / fine structureP2540801P2540801

Duane-Hunt displacement law and Planck's "quantum of action"P2540901P2540901

Absorption of X-raysP2541101P2541101

K and L absorption edges of X-rays / Moseley's law and theRydberg constantP2541201P2541201

Examination of the structure of NaCl monocrystals with differentorientationsP2541301P2541301

X-ray investigation of cubic crystal structures / Debye- Scherrerpowder methodP2541401P2541401

X-ray investigation of hexagonal crystal structures / Debye-Scherrer powder methodP2541501P2541501

Compton scattering of X-raysP2541701P2541701

Complete experiment list see: www.phywe.comComplete experiment list see: www.phywe.com

01200-0201200-02

7 Inorganic Chemistry7 Inorganic Chemistry7.5 Literature


152

154154160160

Organic ChemistryOrganic Chemistry8.18.1 Organic SynthesisOrganic Synthesis8.28.2 Distillation, PurificationDistillation, Purification

8 Organic Chemistry8 Organic Chemistry


153

PrinciplePrinciple

Unlike the other alkali-organyls, lithium organyls - with the ex-ception of methyllithium - show a stronger covalent behaviour.They dissolve rather well in organic solvents, such as diethyl ether,tetrahydrofuran, and alkanes, and they are relatively stable inthese solvents.Wurtz synthesis was developed in 1854 for the preparation ofhigher alkanes based on haloalkanes. Alkyl iodides react the easi-est. The reaction can be controlled best with lithium, since theother alkali metals react much more violently. Wurtz synthesis isoften a side reaction that occurs during organometallic conver-sions.

TaskTask

Investigate the reaction of ethyl iodide with lithium and the fol-lowing reaction of ethyllithium with ethyl iodide.


▪ Alkali-organyls; Lithium organyls▪ Wurtz synthesis; Organometallic compounds


Gasometer 1000 ml 40461-00 1



Gasket for GL25, 8mm hole, 10 pcs. 41242-03 1


Round bottom flask, 100 ml, GL25/12,GL18/8 35842-15 1


Molecular model constuction kit, polymerMolecular model constuction kit, polymerchemistrychemistry


With these big elements (Atoms) for molecular models structuresof chemical compounds can be presented especially vividly also toa greater number of observers.

BenefitsBenefits

▪ Structural elements of shockproof plastic (robust).▪ Diameter of the elements: 38 mm (ostentatious).▪ Chemical elements characterised by internationally usual col-

ours.▪ Angularity of the connections by precisely rivetted push-but-

tons according to the valences of the elements.▪ Transparent connectors: straight for single bonds and curved

for double and triple bonds.

39818-8839818-88

P3101100P3101100 Haloalkanes: Wurtz reaction - lithium organylsHaloalkanes: Wurtz reaction - lithium organyls

Reaction of lithium with ethyl iodide and thefollowing Wurtz reaction of ethyl lithium withethyl iodide.

8 Organic Chemistry8 Organic Chemistry8.1 Organic Synthesis


154

PrinciplePrinciple

Bromine is polarised and, thereby, activated by zinc chloride as aLewis acid. It can attach itself in an ionic manner to the toluenenucleus via several complex intermediate stages. Following a de-hydrobromination, bromotoluene is formed, i.e. the product ofbromination in the nucleus.In the absence of a catalyst and under the influence of light,however, side-chain bromination takes place via radical interme-diate stages. The reaction can be controlled in a targeted mannerby varying the reaction conditions.

TasksTasks

1. Brominate toluene using bromine.2. Change the reaction conditions to optimise your results.3. Distillate the resulting mixture.


▪ Bromine▪ Toluene▪ Lewis acid▪ Bromination▪ Distillation




Separating funnel,50ml,GL18 35853-15 1

Liebig Condenser, with head, GL18/8 35795-15 1

Lab jack, 200 x 230 mm 02074-01 1

Silicone oil 500 ml 31849-50 1

Molecular orbital models, organicsMolecular orbital models, organics


The kit includes all the parts to build up 4 molecular orbital mod-els of the following organic compounds: benzene, ethane, ethyl-ene and acetylene.

BenefitsBenefits

▪ The models show bonding s- and p- orbitals.▪ The concept of hybridisation and delocalisation can be

demonstrated so well.

39837-0039837-00

P3101300P3101300Toluene: Bromination in the nucleusToluene: Bromination in the nucleus

Reaction mechnism of the bromination of tolu-ene.



155

PrinciplePrinciple

When a formaldehyde and ammonia solution mixture is concen-trated a solid white substance results. Ammonia reacts with form-aldehyde (methanal) to hexamethylenetetramine.

TasksTasks

1. Addition of ammonia to acetaldehyde and benzaldehyde.2. Preparation of hexamethylenetetramine (urotropine).


▪ Ammonia▪ Formaldehyde urotropine▪ Hexamethylenetetramine▪ Hydrolysis



Lab jack, 160 x 130 mm 02074-00 1

U tube, 2 side tubes, GL25/8 36959-15 1



Test tube GL25/8, with hose connection 36330-15 2

P3101400P3101400 Aldehydes - reactions with ammoniaAldehydes - reactions with ammonia

Reaction of aldehyde with ammonia.



156

PrinciplePrinciple

This is a model experiment to show the industrial blast furnaceprocess to produce iron from iron(III) oxide. During the experimenta furnace gas flame that is approximately 10 to 20 cm high canbe ignited at the stack outlet. Cavities form in the burning carbonlayer. These cavities collapse over time. Apart from ash and carbonresidues, metallic lumps can also be found in the frame after theend of the experiment. Samples of these lumps lead to the form-ation of hydrogen when they are treated with hydrochloric acid.

TasksTasks

1. Investigate the reduction fo iron(III) oxide to iron(II) oxide.2. Show the blast furnace process in a model experiment.


▪ Iron; Blast furnace process▪ Slug; Production of iron▪ Reduction; Oxidation


Heating mantle for roundbottom flask, 100ml, 230 V,with safety switch 49541-93 1




Water separator GL25/12 35790-15 1


Water separator GL25/12Water separator GL25/12


Water separator to separate two non-miscible liquids with differ-ent densities.


▪ Made of DURAN®▪ With glass cock and GL 25/12 connection and connecting pipe▪ Diameter connecting pipe: 12 mm▪ Graduated; Content: 5 ml

35790-1535790-15

P3101500P3101500Preparation of p-toluenesulfonic acidPreparation of p-toluenesulfonic acid

Reaction of toluene with sulfonic acid.



157

PrinciplePrinciple

In the first part of the experiment, benzaldehyde disproportion-ates under the effect of alkalis to alcohol-soluble benzyl alcoholand water-soluble benzoic acid that precipitates when theaqueous solution is acidified. In the second part, benzaldehydereacts with ethylene glycol to form a cyclic acetal. This ethyleneacetal is resistant against basic and oxidising reagents. In an acidmedium, it once again splits up into its original products. It is be-cause of these characteristics that cyclic acetals are used for block-ing the carbonyl function in preparative, organic chemistry.

TasksTasks

1. Show the Cannizzaro reaction of benzaldehyde under basicconditions.

2. Prepare benzaldehyde ethylene acetal from benzaldehydewith ethylene glycol.


▪ Cannizzaro reaction; Benzaldehyde▪ Acetals; Distillation; Micro distillation







Sec.bottle500ml, 2x Gl18/8,1x 25/12 34170-01 1


Abbe refractometerAbbe refractometer


Abbe refractometer for measuring the refraction index of liquidsand solids with light of 590 nm wavelength (sodium D line) anddetermining average dispersion nC-nF.The refractive index scale also includes an additional scale indic-ating sugar content from 0 - 95 %. The prism and scales can beilluminated by daylight or by a separate lighting unit.

35912-0035912-00

P3101600P3101600 Cannizzaro reaction and reaction of benzaldehyde with ethyleneCannizzaro reaction and reaction of benzaldehyde with ethyleneglycolglycol

Reaction mechanism of the disproportion ofbenzaldehyde to benzyl alcohol and benzoicacid.



158

P3101000P3101000

PrinciplePrinciple

Haloalkanes react with magnesium to the so-called Grignard re-agents in accordance with the general formula RMgX. With X =bromide or iodide, the reaction works best. Chlorides are usuallymore inert and require higher temperatures and longer reactiontimes for the conversion. The compounds that were discovered byVictor Grignard probably exist as dimeric structures.

Haloalkanes: Grignard reagentHaloalkanes: Grignard reagent


P3120500P3120500

PrinciplePrinciple

Like an olefin, ethyne adds bromine to thetrans-1,2-dibromoethene by way of a bromonium ion. Underthe given circumstance, further bromine can be added to thetrans-1,2-dibromoethene to form 1,1,2,2-tetrabromoethane.The tetrabromoethane is the stable final product of this reaction.

The cis-1,2-dibromoethene can result from ethyne as a by-product as well as from the tetrabromoethane as a result of de-halogenation. Three peaks can be distinguished in the gas chro-matogram.

Electrophilic addition of bromine to acetylene (ethyne)Electrophilic addition of bromine to acetylene (ethyne)




159

PrinciplePrinciple

The separation power of a rectification (fractionating) column canbe determined using an appropriate binary mixture whose equi-librium composition is measured in the distillation flask and inthe domed glass head of the distillation apparatus. The number oftheoretical trays can be numerically or graphically obtained fromthe measured values.

TasksTasks

1. Prepare 10 mixtures of methyl cyclohexane and n-heptanewith substance ratios (mole fractions) from 0 to 1 and withstep width of approximately 0.1. To record a calibrationcurve, determine the refractive indices of the mixtures andplot them against the mole fractions.

2. Distill a mixture of methyl cyclohexane and n-heptane in arectification column with total reflux until an equilibriumhas been established. Determine the composition of the con-densate and the number of theoretical trays in the columnfor a throughput of 500 and 1000 ml/h.


▪ Bubble tray column; Rectification▪ Raoult's law; Henry's / Dalton's law▪ Boiling-point diagram; Reflux ratio


Set rectification plant, 230 V 35918-88 1


Data acquisitation set for set rectificationplant, 230 V 35918-50 1



Set rectification plant, 230 VSet rectification plant, 230 V


Distillation plant with a height of 235 cm to the demonstrationand processing the principles of countercurrent-distillation (phaseequilibrium of muticomponent systems) or to the preparative sep-aration of mixtures difficult to separate

BenefitsBenefits

This set allows to execute the measurements in a didactical clearand easy way:

▪ Complete insight into all running processes, because all com-ponents have an evacuated, but not silvered isolating-coat

▪ High separation efficiency through 2 large packed columns ( h= 400 mm); Simple withdrawal of samples through 2 columnintermediate pieces

▪ Secure, because the high-efficiency condensor of the columnhead also condense high-volatile liquids

▪ Simple adjustment of thereflux ratio's through onehand-con-trolled column head

35918-8835918-88

P3031501P3031501 Rectification - the number of theoretical trays in a distillationRectification - the number of theoretical trays in a distillationcolumncolumn

Equilibrium diagram.

Fractional distillation with the bubble tray column (withFractional distillation with the bubble tray column (withCobra3)Cobra3)

P3031640P3031640

8 Organic Chemistry8 Organic Chemistry8.2 Distillation, Purification


160

PrinciplePrinciple

An elegant and simple apparatus for carrying out water vapourdistillations: the advantage of this arrangement is that it elimin-ates the need for a separate vapour generator, making it possibleto operate with a single heat source (other set-ups require two).The vapour is generated in the outer chamber and then passesthrough the inner chamber. Due to the structural arrangement,the inner chamber is heated directly by the vapour generated inthe outer chamber. This also eliminates the possibility of over-heating the substances being extracted.Parts of plants suitable for the extraction of essential oils includeorange peel and cloves, for example.

TaskTask

Extract ethereal oils from parts of plants e g. orange peel andcloves using steam distillation.


▪ Distillation▪ Steam distillation▪ Etheral oils▪ Flavour





Lab jack, 160 x 130 mm 02074-00 1

Insert w.ext.tube f.glass jack. 02615-06 1

Cooling jacket, GL 25/8 34880-01 1

Heating apparatus for glass jacket systemHeating apparatus for glass jacket system


Hot plate. For a uniform and hence material protecting heating ofcylindrical bodies or devices made of metal, ceramic or glass.


▪ Power requirement 500 W max.▪ Surface temperature 500 °C▪ Mains supply: 230 V, 50...60 Hz▪ Dimensions (mm): 160 x 95 x 90 mm▪ Items suitable for heating: minimum length: 130 mm, dia-

meter: 36...100 mm

32246-9332246-93

P3031251P3031251Steam distillationSteam distillation

Orange peel and cloves are both very suitablefor winning ethereal oils.



161

PrinciplePrinciple

If the alcohol content of a wine is determined directly with an al-cohol meter (hydrometer), the resulting alcohol content reading isapproximately 0% by volume. This is due to the composition of thewine. The effect of the alcohol on the density is cancelled out byother components such as sugars, acids, essential oils, etc..For this reason, in order to determine alcohol content by density,the alcohol must be separated out by means of distillation prior tothe determination. This corresponds to the official method whichcurrently applies for measuring alcohol in wines. First the wine istitrated to neutrality against bromothymol blue. After transfer tothe distillation apparatus, two thirds of this wine sample is dis-tilled off into the receiver flask. Subsequently the distillate is filledback up to the original volume again. Now the density is measuredwith a pycnometer or hydrometer.

TaskTask

Distillate a sample of wine to determine the content of ethanol.


▪ Ethanol; Distillation


Large-scale display, digital, RS-232 port 07157-93 1

Cobra4 Display-Connect, Set of transmitterand receiver for using the Cobra4 Mobile-Link with large-scale displays 12623-88 1




Large-scale display, digital, RS-232 portLarge-scale display, digital, RS-232 port


Special four-digit large-format display for presenting the meas-urement data supplied by the new Cobra4 Mobile-Link with Co-bra4 Display-Connect, the Cobra3 Com-Unit, the PHYWE hand-heldmeasuring instruments and Sartorius or Scaltec balances equippedwith data interfaces.

07157-9307157-93

P1308962P1308962 Distillation - determination of the alcohol content of wine (withDistillation - determination of the alcohol content of wine (withCobra4)Cobra4)

Content of wine: 82 % water, 11 % ethanol, 4% sugar and glycerol, 2 % acids and salts, 1 %rest.



162

PrinciplePrinciple

Different methods to separate liquid mixtures are shown. In thefirst part a mixtures of immiscible or only poorly miscible liquidsis separated. In the next example a substance that is dissolved ina certain solvent is better soluble in another solvent and the sep-aration is achieved via shaking. Relatively stable emulsions can'tbe separated by liquid-liquid extraction alone, since the emulsi-fied liquids will not unmix with a sufficiently sharp delineation.However, separation can be achieved by centrifugating the emul-sion in a first step. In this case, the emulsion is unmixed underthe influence of the centrifugal force and it can then be separatedby liquid-liquid extraction.

TasksTasks

1. Separation by liquid-liquid extraction.2. Separation shaking and liquid-liquid extraction.3. Separation of an emulsion by centrifugation and liquid-li-

quid extraction.


▪ Separation procedure; Liquid-liquid extraction▪ Shaking; Centrifugation; Emulsion


Manual centrifuge f. 4 specimens 45052-00 1



Cyclohexane 1000 ml 31223-70 1


Separatory funnel 250 ml pear-sh. 36884-00 1

Manual centrifuge for 4 specimensManual centrifuge for 4 specimens


Manual centrifuge with for 4 specimens.

BenefitsBenefits

▪ To attach to the work bench▪ Combined plastic / metal housing▪ The gearbox is self lubricating and very smooth with sleeves

made of plastic▪ Comes with four centrifuge tubes


▪ Speed: 3,000 rpm▪ Centrifuge tube: contents 15 ml, conical, ungraduated

45052-0045052-00

P3120100P3120100Separation of mixtures of liquids and of solutions by extraction,Separation of mixtures of liquids and of solutions by extraction,stirring, centrifugationstirring, centrifugation

Separation by liquid-liquid extraction.



163

PrinciplePrinciple

The discussion of healthy nutrition focuses on the fat contentof foodstuffs. For this reason, it is important to know the exactfat content of individual foodstuffs. The experiment shown herepresents a method for the quantitative determination of the fatcontent of foodstuffs by extraction using a Soxhlet apparatus. Thissmall size of this Soxhlet extractor makes it possible to extractsmall quantities using extremely small amounts of solvent.

TaskTask

Calculate the fat content of a sausage using soxhlet extraction.


▪ Soxhlet apparatus▪ Fat extraction▪ Food chemistry▪ Food analysis


Drying oven UNB200, timer, 32 l 46959-93 1




Micro distil.app., GL18/8, with head 35818-15 1

Soxhlet attachment, GL25/12 35809-15 1


Soxhlet attachment, GL25/12Soxhlet attachment, GL25/12


The sample for extraction is placed in an extraction thimble madeof compressed filterpaper, the thimble is slipped into the Soxhletattachment and the attachment is fitted onto a flask containingan appropriate solvent. A reflux condenser is fitted to the top ofthe attachment and the solvent is heated so that it evaporates.Solvent vapour ascends up the vapour by-pass tube into the refluxcondenser, where it condenses and drops back down into the ex-traction thimble.

Here it dissolves out soluble matter from the sample and collectsin and around the thimble until the solvent level here reaches thehighest point of the siphon tube. The whole of this solvent is thenautomatically siphoned back into the flask and the procedure re-peats itself. In this way, countless extraction steps can be carriedout simply and successively, whereby the components extractedfrom the sample are concentrated in the flask.

35809-1535809-15

P3120200P3120200 Quantitative determination of fat / Soxhlet extractionQuantitative determination of fat / Soxhlet extraction

Schematic setup of the experiment.



164

P3120400P3120400

PrinciplePrinciple

Chromatographic separation processes are very important foranalytical chemistry. Their relatively simple technique and thepossibility to separate even the smallest portions of mixtures ex-plain the rapid development of these processes. There are nu-merous variations of this method.

As a result, the optimum chromatographic separation methodcan be found for nearly every separation task. The method thatis described here can be used to demonstrate the fundamentalprinciples and possibilities of this method with relatively simplemeans.

Chromatographic separation processes: Thin layer chromatographyChromatographic separation processes: Thin layer chromatography


P3031760P3031760

PrinciplePrinciple

Chromatographic procedures allow a separation of substancemixtures with the aid of a stationary separation phase and a mo-bile phase. In gas chromatography the mobile phase is a gas. Themobile phase, to which the mixture to be separated is added,transports the substance mixture through the separation columnat a constant flow rate. Interactions occur between the mobilephase and the stationary phase. The establishment of equilibriabetween the stationary phase and the different substances (dis-tribution equilibria, adsorption-desorption equilibria) results indifferent migration rates of the individual components.

Chromatographic separation processes: Gas chromatography (with Cobra4)Chromatographic separation processes: Gas chromatography (with Cobra4)


P3120300P3120300

PrinciplePrincipleIn this investigation, a uniformly green raw extract of freshleaves is first separated into different fractions by means ofcolumn chromatography. To do so, the extract is added to acolumn filled with starch and drawn through the column underslightly reduced pressure (to increase the flow rate of the mobilephase) with ligroin as the eluent. A separation occurs in a clearlyrecognisable, broad, yellow area and in a narrow, green band.This means that the xanthophylls (yellow) are separated from thechlorophylls (green). If the vacuum is reduced during the separ-ation, the separation is much better, but then separation alsotakes considerably longer.

Column chromatography - separation of leaf pigmentsColumn chromatography - separation of leaf pigments




165

Find further experiments in the following manual:Find further experiments in the following manual:

TESS Chemistry manual Organic ChemistryTESS Chemistry manual Organic Chemistry



The decomposition of organic substancesP1035700P1035700

The detection of carbon with lime waterP1035800P1035800

The detection of carbon by oxidationP1035900P1035900

The detection of oxygenP1036000P1036000

The detection of nitrogenP1036100P1036100

The detection of sulphurP1036200P1036200

The Beilstein testP1036301P1036301

Marsh gasP1036400P1036400

Preparation of methaneP1036500P1036500

Homologous series of alkanesP1036600P1036600

Reactivity of alkanesP1036700P1036700

Preparation of etheneP1036800P1036800

Preparation of ethyneP1036900P1036900

NaphthaleneP1037000P1037000

Petroleum depositsP1037100P1037100

Fractional distillationP1037200P1037200

Properties of petroleum fractionsP1037300P1037300

Petroleum combustionP1037400P1037400

Cracking of petroleumP1037500P1037500

Removal of paraffin by extractionP1037600P1037600

Removal of paraffin with ureaP1037700P1037700

Alcoholic fermentationP1037800P1037800

Production of methanol "wood spirit"P1037900P1037900

The ascending tube testP1038000P1038000

Alcotest tubesP1038100P1038100

DistillationP1038200P1038200

The borax testP1038300P1038300

The iodoform testP1038400P1038400

The properties of the homologous seriesP1038500P1038500

Polyhydric alcoholsP1038600P1038600

The oxidation of alkanolsP1038700P1038700


01837-0201837-02

Cracking of petroleum - P1037500Cracking of petroleum - P1037500



166

168168172172174174176176180180

Industrial ChemistryIndustrial Chemistry9.19.1 GasesGases9.29.2 SaltsSalts9.39.3 Disposal, Environment ProtectionDisposal, Environment Protection9.49.4 PetrochemistryPetrochemistry9.59.5 MetallurgyMetallurgy

9 Industrial Chemistry9 Industrial Chemistry


167

PrinciplePrinciple

In an electric arc nitrogen and oxygen are caused to react witheach other. In a first step, this leads to the generation of colour-less nitrogen monoxide that continues to react with oxygen, thusforming the red-brown nitrogen dioxide. When the gas reacts withwater in the presence of even more oxygen, the result is nitric acidthat causes the litmus solution to turn red.

TasksTasks

1. Demonstrate the reaction of nitrogen and oxygen using highvoltage.

2. Investigate the reaction of nitrogen dioxide with water.


▪ Nitrogen oxides▪ Air▪ Nitrogen monoxide▪ Nitrogen dioxide▪ Nitric acid



Coil, 10000 turns 06519-01 1

Clamping device 06506-00 1

Iron core, U-shaped, laminated 06501-00 1

Coil, 150 turns, short 06520-01 1

Bar electrodes, HV, insul.,1 pair 45253-00 1

Iron core, short, laminated 06500-00 1






▪ Adjustable current limit between 0...5 A▪ LED display for constant current operationn▪ Permantely short-circuit proof & protected against exterior

voltages▪ Alternative voltage output:▪ Multitap transformer 2...15 V, outputs galvanically separated

from mains grid▪ Full load capacity (5 A), even if direct current is supplied sim-

ultaneously

13500-9313500-93

P3110100P3110100 Obtaining nitrogen oxides by burning airObtaining nitrogen oxides by burning air

Chemical process for the production of nitricacid.

9 Industrial Chemistry9 Industrial Chemistry9.1 Gases


168

PrinciplePrinciple

The Haber-Bosch process was the first large-scale technical meth-od for producing nitrogen compounds based on the nitrogen inthe air. The formation of ammonia benefits from a falling temper-ature and rising pressure since it is an exothermic reaction thatis accompanied by a decrease in volume. At room temperature,however, the reaction rate would be so small that it could not bemeasured. In addition, current catalysts are only effective at high-er temperatures (approximately 400-500 °C). If these temperat-ures are used at normal pressure, the ammonia yield is approxim-ately 0.1% by volume. Technical processes, in which the pressureis increased in a continuous process, yield approximately 11% (es-tablishment of equilibrium at 200 bar: 17.6% of ammonia).

The setup that is used here can be used to demonstrate the Haber-Bosch process in a simplified manner. The optimum conditionsthat are necessary for the process cannot be realised with themeans that are available at schools or it would be extremely diffi-cult to realise them.

TaskTask

Demonstrate the principle of the Haber-Bosch process.


Ammonia preparation from the elements (Haber-Bosch process)


Steel cylinder hydrogen, 2 l, filled 41775-00 1

Steel cylinder nitrogen, 2 l, filled 41777-00 1

Bead catalyst, Pt-Pd-Al-oxide 10 g 31763-03 1

Reducing valve for nitrogen 33483-00 1


Carl Bosch (left) and Friedrich Bergius (right)Carl Bosch (left) and Friedrich Bergius (right)


P3110200P3110200Ammonia preparation from the elements (Haber-Bosch process)Ammonia preparation from the elements (Haber-Bosch process)

Schematical setup of the experiment.



169

PrinciplePrinciple

In the presence of a suitable catalyst and while giving off heat,ammonia-air mixtures burn and form nitrogen monoxide and wa-ter. Nitrogen monoxide reacts immediately with the excess oxy-gen, thereby forming nitrogen dioxide.

At higher temperatures, nitrogen monoxide is decomposed intonitrogen and oxygen. This is why the contact with the catalystmust be very brief. In the presence of water and oxygen, nitrogendioxide forms nitric acid. On a large industrial scale, the com-bustion of ammonia with atmospheric oxygen is performed undercontact with platinum (Ostwald process). The resulting nitric acidis used for the production of fertilisers and numerous other chem-ical products.

TaskTask

Burn an ammonia-air mixture in the presence of a catalyst(platinum-palladium-aluminium-oxide beads) and prove the res-ulting nitrogen oxide.


▪ Ostwald process; Ammonia; Nitrogen dioxide▪ Nitrogen monoxide; Nitric acid


Bead catalyst,Pt-Pd-Al-oxide 10 g 31763-03 1



Glycerol 250 ml 30084-25 1

Test tube GL25/8, with hose connec. 36330-15 2

Water jet pump, plastic 02728-00 1

P3110300P3110300 Combustion of ammonia to produce nitrogen dioxide - OstwaldCombustion of ammonia to produce nitrogen dioxide - Ostwaldprocessprocess

Combustion process of gas/air mixtures.



170

PrinciplePrinciple

The contact process is currently used in the chemical industryto produce sulphuric acid in the high concentrations needed forindustrial processes. In this model experiment, platinum-palladium-aluminium-oxide beads are employed as a catalyst forthe reaction.

TasksTasks

1. Oxidise sulphur dioxide to sulphur trioxide.2. Use the sulphur trioxide to produce sulphuric acid.


▪ Sulphur trioxide▪ Sulphuric acid▪ Contact process▪ Oxidation▪ Redox reaction



Bead catalyst, Pt-Pd-Al-oxide 10 g 31763-03 1





Funnel for gas generator, 50 ml, GL18Funnel for gas generator, 50 ml, GL18


Funnel for gas generator


▪ Lower connecting pipe diameter: 12 mm▪ Outer Diameter Gasolive: 8 mm▪ Overall height: approx 270 mm▪ Contents: 50 ml

35854-1535854-15

P3110400P3110400Sulphur trioxide - the sulphuric acid contact processSulphur trioxide - the sulphuric acid contact process

Formation of sulfuric acid during the experi-ment.



171

PrinciplePrinciple

Natural gypsum has the formula CaS04•2H20. When it is heatedabove 130 °C, part of the crystal water is released. The result isa so-called hemihydrate CaS04•1/2H20. Following the absorptionof water, the hemihydrate is once again converted into a dihy-drate. During this process, needle-shaped crystals are formed. Thisis why barium sulphate precipitates when barium ions are addedto sulphate ions, even if the concentrate of sulphate ions is as lowas it is in the present case. This reaction is generally used for thedetection of sulphate ions.

TasksTasks

1. Investigate the properties of gypsum.2. Detect sulphate ions in solution using barium-solution.


▪ Sulphate▪ Gypsum▪ Sulphuric acid▪ Gypsum calcination


Glass tube f.calcin. of gypsum 45145-00 1


Gypsum, crude pieces, 250 g 48273-25 1

Hydrochloric acid 37 %, 1000 ml 30214-70 1

Barium chloride 250 g 30033-25 1

Calcium sulphate precipit. 100 g 31182-10 1

P3110700P3110700 Salts of sulphuric acid - sulphatesSalts of sulphuric acid - sulphates

Schematic construction of the experiment.

9 Industrial Chemistry9 Industrial Chemistry9.2 Salts


172

PrinciplePrinciple

The electrolysis of molten sodium chloride to obtain chlorine andsodium, which can be further processed to produce sodium hy-droxide, is an important industrial-scale process. The experimentdepicted here can be used for a simple demonstration of the im-portant steps in this process. Due to the high melting point ofsodium chloride, however, lower-melting lead chloride is used asthe raw material in the model experiment.

TaskTask

Demonstration the electrolysis of molten sodium chloride to ob-tain chlorine and sodium.


▪ Electrolysis▪ Melt▪ Chlorine▪ Starch-iodine solution


Multimeter ADM2, demo., analoque 13820-00 1



Shelf with hanging device 45505-00 1

Wash tube with fritted disc 36699-00 1

Lead-II chloride 500 g 31117-50 1


Crystal-lattice model sodium chlorideCrystal-lattice model sodium chloride


High quality crystal-lattice model of sodium chloride consisting ofcoloured wooden balls and metallic links; the model will be de-livered completely fixed.


▪ Scale to real crystals: 1 : 250 million▪ Diameter of the balls: approx. 20 mm

40014-0040014-00

P1310500P1310500Molten-salt electrolysisMolten-salt electrolysis

Oxidation/reduction process during the experi-ment.

9 Industrial Chemistry9 Industrial Chemistry9.2 Salts


173

PrinciplePrinciple

German coal contains an average of one tonne of sulphur per100 tons of coal. During combustion, this generates in about twotonnes of sulphur dioxide. Thus, a large 700 megawatt powerplant which burns about 200 tons of coal per hour produces about100 tons of sulphur dioxide per day. These days of course, sucha large quantity of a pollutant can no longer be simply releasedinto the air, therefore these flue gases have to be desulphurised.This model experiment provides a simple demonstration of thechemical processes of flue gas desulphurisation as it is carried outin power plants today. The clear, compact setup and the simpli-fications undertaken relative to industrial scale desulphurisationmake it easy to understand the process.

TaskTask

Clean flue gas using limestone and describe the underlying chem-ical process.


▪ Sulphur; Limestone; Gypsum▪ Desulphurisation; Flue gas



Secure bottle, 500 ml, 2 x Gl 18/8, 1 x 25/12 34170-01 1

Apparatus carrier with fix. magnet 45525-00 1


Combustion tube 200 mm, quartz, IGJ19 33947-00 1



Panel for complete experimental setupsPanel for complete experimental setups


Panel with regular punching to receive the hooks of the holder ho-rizontal or vertical positioning in the frame, one panel is necces-sary for each experiment


▪ Material: sheet steel, powder painted with good mechanicaland chemical resistance

▪ Dimensions: 65 x 48.8 x 2.5 cm

45510-0045510-00

P1310000P1310000 Model experiment on the desulphurisation of flue gasModel experiment on the desulphurisation of flue gas

Reaction of limestone with sulphur dioxide togypsum.

9 Industrial Chemistry9 Industrial Chemistry9.3 Disposal, Environment Protection


174

PrinciplePrinciple

Smoke consists of particles of solid substances suspended in gas.Fog is made up of suspended droplets. In cigarettesmoke, as in many industrial processes, smoke and fog are fre-quently present together. The removal of particles contained ingases - predominately waste gases - is increasingly gaining inimportance, both in everyday life and industrially, because fre-quently the particles and the substances absorbed on them aretoxic. Well known examples are adsorbed polycyclic aromatics onsoot particles in diesel exhaust, and dioxins, heavy metals and ra-dioactive elements in waste gasesfrom power stations and waste incinerators. The deposited filterdusts are highly toxic, and must be treated as hazardouswaste. The experimental set-up used here also enables constitu-ents of cigarette smoke to be semi-quantitatively deposited evenin quite large amounts, so that they can be extracted with lightpertrol and be examined.

TasksTasks

Clean cigarette smoke using high voltage.


▪ Smoke; Electric filter; Electrostatic filter; Exhaust gas filter





Insert with joining tube 02615-04 1









▪ Selectable positive and negative polarity. 3-figure LED display.▪ Outputs short-circuit proof. Special safety sockets.▪ Modern plastic housing, impact resistant, easy to service, light

stackable with retractable carrying handle and stand.

13670-9313670-93

P1309200P1309200Electrostatic flue gas cleaningElectrostatic flue gas cleaning

Smoking chimneys.

9 Industrial Chemistry9 Industrial Chemistry9.3 Disposal, Environment Protection


175

PrinciplePrinciple

In countercurrent distillation (rectification) using a column, therising vapour can enter into interactions with the condensate. Inthis manner, a fractional distillation, i.e. a distillation in severalsteps for the separation of substances with similar boiling points,can be performed in a single apparatus. If bubble tray columnsare used condensate can be removed from the individual bubbletrays.

TasksTasks

1. Investigate the mode of operation of a fractionating toweron a two-stage bubble tray column. Distil a mixture of threen-alcanes first with total reflux and then without any reflux.

2. Subsequently, examine and compare the initial mixture, thesump product, the head products and the condensates ofboth trays gas chromatographically.


▪ Bubble tray column▪ Rectification▪ Continuous and discontinuous distillation▪ Vapour pressure▪ Vaporisation▪ Condensation▪ Raoult's law▪ Gas chromatography


Cobra3 Chem-Unit, USB 12153-50 1


Control unit gas chromatograph 36670-99 1

Bubble tray column, model, with 2 trays 35914-15 1

Steel cylinder helium, 2 l, filled 41776-00 1




P3031640P3031640 Fractional distillation with the bubble tray column (with Cobra3)Fractional distillation with the bubble tray column (with Cobra3)

Temperature-time curve for a fractional distilla-tion.

Fractional distillation with the bubble tray column (withFractional distillation with the bubble tray column (withCobra4)Cobra4)

P3031660P3031660

9 Industrial Chemistry9 Industrial Chemistry9.4 Petrochemistry


176

PrinciplePrinciple

The separation power of a rectification (fractionating) column canbe determined using an appropriate binary mixture whose equi-librium composition is measured in the distillation flask and inthe domed glass head of the distillation apparatus. The number oftheoretical trays can be numerically or graphically obtained fromthe measured values.

TasksTasks

1. Prepare 10 mixtures of methyl cyclohexane and n-heptanewith substance ratios (mole fractions) from 0 to 1 and withstep width of approximately 0.1. To record a calibrationcurve, determine the refractive indices of the mixtures andplot them against the mole fractions.

2. Distill a mixture of methyl cyclohexane and n-heptane in arectification column with total reflux until an equilibriumhas been established. Determine the composition of the con-densate and the number of theoretical trays in the columnfor a throughput of 500 and 1000 ml/h.


▪ Bubble tray column; Rectification; Raoult's law▪ Henry's / Dalton's law; Boiling-point diagram; Reflux ratio


Set rectification plant, 230 V 35918-88 1



Data acquisitation set for set rectificationplant, 230 V 35918-50 1

Set rectification plant, 230 VSet rectification plant, 230 V


Distillation plant with a height of 235 cm to the demonstrationand processing the principles of countercurrent-distillation (phaseequilibrium of muticomponent systems) or to the preparative sep-aration of mixtures difficult to separate

BenefitsBenefits

▪ Complete insight into all running processes, because all com-ponents have an evacuated, but not silvered isolating-coat

▪ High separation efficiency through 2 large packed columns ( h= 400 mm)

▪ Simple withdrawal of samples through 2 column intermediatepieces

▪ Secure, because the high-efficiency condensor of the columnhead also condense high-volatile liquids

▪ Simple adjustment of thereflux ratio's through onehand-con-trolled column head

Equipment and technical DataEquipment and technical Data

▪ It will be delivered complete with tripod material and all ne-cessary small hardware items.

▪ 6 l four-neck flask; Electrical heating hood▪ Power regulator; 2 packed columns▪ Packing bodys (wire mesh rings); 2 column intermediate

pieces; Column head; Separate product condensor▪ Rack system for the set-up of the plant▪ Small hardware items; CD with literature

35918-8835918-88

P3031501P3031501Rectification - the number of theoretical trays in a distillationRectification - the number of theoretical trays in a distillationcolumncolumn

Equilibrium diagram.



177

PrinciplePrinciple

Under the influence of energy, e.g. heat, light, and electric dis-charge, all chemical compounds can be broken down into smallerfractions. The reaction can continue up to the elements them-selves. In general, low-volatile crude oil components are disinteg-rated as of approximately 400 °C. The presence of a catalyst lowersthe activation energy of this cracking reaction so that the de-composition products are formed already at lower temperatures.Saturated carbohydrates are then transformed into smaller satur-ated and unsaturated molecules. Cycloalkanes are dehydrated toaromatic compounds, straight-chain molecules to branched-chainmolecules, and branched-chain molecules to cyclic molecules.

TaskTask

Investigate the cracking of hydrocarbons using a model experi-ment.


▪ Cracking▪ Hydrocarbons▪ Catalyst



Bead catalyst, 500 g 31761-50 1

Vacuum adaptor, straight, GL25/12 35806-15 1

Gas-syringe holder with stop 02058-00 1

Sea sand, purified 1000 g 30220-67 1

Bromine 100 ml 30046-10 1

Molecular model construction kit, organicMolecular model construction kit, organicchemistrychemistry


With these big elements (atoms) for molecular models structuresof chemical compounds can be presented especially vividly also toa greater number of observers

BenefitsBenefits

▪ Structural elements of shockproof plastic▪ Diameter of the elements: 38 mm (ostentatious)▪ Chemical elements characterised by internationally usual col-

ours▪ Angularity of the connections by precisely rivetted push-but-

tons according to the valences of the elements▪ Transparent connectors: straight for single bonds and curved

for double and triple bonds

39821-8839821-88

P3110800P3110800 Cracking of hydrocarbonsCracking of hydrocarbons

Schematic setup of the experiment.



178

PrinciplePrinciple

The heat of reaction generated during the complete combustion of1000 g of solid or liquid fuel is known as the calorific value H. Inthe case of complete combustion of nutritional fats, the gross cal-orific value can also be determined. In order to ensure completecombustion, the reaction takes place under oxygen. The heat gen-erated during the combustion of a specific amount of fuel is ab-sorbed by a glass jacket calorimeter of known heat capacity. Thecalorific value of the test substance can be calculated from thetemperature increase in the calorimeter.

TaskTask

Determine the calorific value of heating oil and the gross calorificvalue of olive oil.


▪ Heat of reaction▪ Heat of combustion▪ Enthalpy of combustion▪ First law of thermodynamics







Combustion lance for gases 02613-00 1


P3021701P3021701Determination of the heating value of fuel oil and of the calorificDetermination of the heating value of fuel oil and of the calorificvalue of olive oilvalue of olive oil

Equation to calculate the calorific value (offuels) and the gross calorific value (of food-stuffs).



179

PrinciplePrinciple

Metallography is the art of preparing metallic samples by grinding,polishing and eventual etching for subsequent microscopic exam-ination. Grinding and polishing is to prepare the specimen sur-face so as to enable the microstructure to be revealed by a suitableetching procedure.

TasksTasks

1. Check the six metal specimens by means of the magnifier forany coarse defects.

2. Grind and polish the samples according to the general rulesand the detailed instructions given, considering the hardnessand ductility data and the basic processing guidelines speci-fied.

3. Evaluate the influence of the individual process parameterson the surface quality obtained in the intermediate stepsand after the final polishing.

4. Try to optimise the grinding and polishing procedures.


▪ Grinding; Polishing▪ Metallographic preparation; Ductility


Grinding and polishing machine, 230 V 200/250 mm, 50-600 rpm, variable 70000-93 1

Ultrasonic cleaning bath, RK100H 46423-93 1

Diamantstick 6 µm, 25 g 70050-04 1

Grinding and polishing wheel Al, 200 mm 70000-11 1

Polishing cloth Ø 200 mm, METAPO-P, 10 pcs.for 10-6 micron diamonds 70002-03 1

Polishing cloth Ø 200 mm, METAPO-B, 10 pcs.for 3-1 micron diamonds 70003-03 1

Polishing cloth Ø 200 mm, METAPO-V, 10 pcs.for 1-0,1 micron diamonds 70004-03 1

Grinding and polishing machine, 230 VGrinding and polishing machine, 230 V200/250 mm, 50-600 rpm, variable200/250 mm, 50-600 rpm, variable

Function and applicationFunction and application

Grinding and polishing machine to prepare metallographicsamples.

BenefitsBenefits

Variable grinding speed to prepare hard and soft samples.


▪ Diameter grinding platen: 200 and 250 mm, respectively▪ Speed: 50-600 rpm▪ Connected power: 60 W▪ Power supply : 230 VAC▪ Dimensions (L x B x H): 380 x 690 x 340 mm▪ Weight: 30 kg

70000-9370000-93

P5510100P5510100 Metallographic sample preparation - grinding and polishingMetallographic sample preparation - grinding and polishing

Surface condition of brass sample after step 1(MD-Primo 220; Lubricant: water; Time: 2 min;Speed: 300 rpm), Magnification: 100x.

9 Industrial Chemistry9 Industrial Chemistry9.5 Metallurgy


180

PrinciplePrinciple

Chemical etching is the most common method for contrastingpolished metal surfaces to reveal structural details of pure metalsand alloys. The precondition for a good result in etching is a care-fully polished and clean surface. The experiment describes the ba-sic procedure, gives some recipes and presents a few pictures ofseveral metal structures and phases.

TasksTasks

1. Check the six metal specimens polished by means of the mi-croscope to see if any macroscopic or microscopic structuralfeatures can be noticed.

2. Prepare the etching solutions and etch the specimens ac-cording to the instructions.

3. Examine the specimen surfaces as to whether the structuraldetails have been satisfactorily revealed.


▪ Etching; Reveal crystallographic structure▪ Micrography; Metallographic phases; Metal microscopy


Microscope with incident and transmittedillumination set with USB CAM, 230 V formetallographic appl. 62244-88 1

Press for polished section 62244-15 1

Compact Balance, OHAUS TA 501, 500 g / 0.1g, 230 V 49243-93 1

Sample set metallurgy containing 8 metallsamples 70001-01 3

Labels GHS, blank, chemistry, 20 pcs. 38687-01 1

Isopropyl alcohol, 1000 ml 30092-70 1

Pasteur pipettes, 3 ml, PE, 500 pcs. 36616-00 1

P5510200P5510200Metallographic sample preparation - chemical etchingMetallographic sample preparation - chemical etching

Copper, etched in sol. 5, grain contrast/precip.etching, magnification approx. 100x.



181

PrinciplePrinciple

This is a model experiment to show the industrial blast furnaceprocess to produce iron from iron(III) oxide. During the experimenta furnace gas flame that is approximately 10 to 20 cm high canbe ignited at the stack outlet. Cavities form in the burning carbonlayer. These cavities collapse over time. Apart from ash and carbonresidues, metallic lumps can also be found in the frame after theend of the experiment. Samples of these lumps lead to the form-ation of hydrogen when they are treated with hydrochloric acid.

TasksTasks

1. Investigate the reduction fo iron(III) oxide to iron(II) oxide.2. Show the blast furnace process in a model experiment.


▪ Iron▪ Blast furnace process▪ Slug▪ Production of iron▪ Reduction▪ Oxidation


Steel cylinder Hydrogen, 2 l, full 41775-00 1

Support, with closed-circuit pipeline 36688-01 1

Hot air blower with adaptor 36688-93 1





P3110500P3110500 Preparation of iron from oxidic ores (blast furnace process)Preparation of iron from oxidic ores (blast furnace process)

Iron oxide is reduced to iron by hydrogen,which reacts with hydrochloric acid with evolu-tion of hydrogen.

Redox reactions between metals and metal oxidesRedox reactions between metals and metal oxides(thermite process)(thermite process)

P3110600P3110600



182

184184188188193193

Biochemistry and BiotechnologyBiochemistry and Biotechnology10.110.1 BiochemistryBiochemistry10.210.2 BiotechnologyBiotechnology10.310.3 LiteratureLiterature

10 Biochemistry and Biotechnology10 Biochemistry and Biotechnology


183

PrinciplePrinciple

Amino acid molecules carry both acid and amino groups. They cantherefore form both acidic anions and basic cations. The pH atwhich these two types of iones are both present in the same con-centration is called the isoelectric point.

TaskTask

This isoelectric point is to be determined by recording the titrationcurve for the amino acid glycine.


▪ Isoelectric point▪ Acidic anions▪ Basic cations▪ Zwitterions▪ Equivalence (inflection) points▪ pKs value▪ Titration▪ Motor piston burette








Precision Balance, Sartorius TE 212, 210 g /0,01 g, 230V 48833-93 1

P4120160P4120160 Determination of the isoelectric point of an amino acid (glycine)Determination of the isoelectric point of an amino acid (glycine)(with Cobra4)(with Cobra4)

Titration curve for hydrochloric acid glycinesolution against 1 mol/l NaOH.

10 Biochemistry and Biotechnology10 Biochemistry and Biotechnology10.1 Biochemistry


184

PrinciplePrinciple

The enzymatic hydrolysis of urea in aqueous solution liberates car-bon dixide and ammonia. The ions of these compounds increasethe conductivity of the solution. Conductivity measurements canso be made to determine the rate of hydrolysis of urea by the en-zyme urease at various substrate concentrations.

TaskTask

The Michaelis constant can then be calculated from these values.


▪ Michaelis constant▪ Enzymatic hydrolysis of urea▪ Conductivity measurement▪ Bodenstein principle▪ Enzyme-substrate complex▪ Lineweaver-Burk plot







Urease soln.in 50% glycerol, 10ml 31924-03 1

Precision Balance, Sartorius TE 212, 210 g /0,01 g, 230 V 48833-93 1



The Cobra4 Sensor Unit, Conductivity/Temperature (Pt1000), is amicrocontroller-based measuring recorder with a 5-pin diodesocket for connecting conductance measuring sensors with a cellconstant of K = 1.00/cm or Pt1000 thermocouples.

BenefitsBenefits

▪ Measure conductivity or temperature - multipurpose-sensor▪ The Cobra4 sensor may be connected directly to the Cobra4


12632-0012632-00

P4120360P4120360Determination of the Michaelis constant (with Cobra4)Determination of the Michaelis constant (with Cobra4)

Conductivity-time-diagram of the urea hydro-lysis by urease.



185

PrinciplePrinciple

The enzymatic hydrolysis of urea in aqueous solution liberates car-bon dioxide and ammonia. The ions of these compounds increasethe conductivity of the solution.

TasksTasks

Conductivity measurements enable the rate of hydrolysis of ureaby the enzyme urease to be determined at various substrate con-centrations. Inhibition of the enzyme by the substrate occures atexcessive substrate concentrations.


▪ Substrate inhibition▪ Enzymolysis of urea▪ Conductivity-time plot▪ Reaction velocity of enzymatic hydrolysis








Urease soln.in 50% glycerol,10ml 31924-03 1




As soon as a Cobra4 sensor is connected to a PC, irrespective ofwhether by Cobra4 Wireless or Cobra4 USB Link, the "measureCo-bra4" software opens completely automatically and shows theconnected sensors, the required measuring windows and the cur-rent measuring data.

Measurement recording is then started with a single CLICK.

This all takes under 40 seconds!

14550-6114550-61

P4120460P4120460 Substrate inhibition of enzymes (with Cobra4)Substrate inhibition of enzymes (with Cobra4)

The dependence of the rate of enzymolysis onthe concentration.



186

P4120560P4120560

PrinciplePrinciple

The enzymatic hydrolysis of urea in aqueous solutions liberatescarbon dioxide and ammonia. The ions of these compounds in-crease the conducitivity of the solution.

TaskTask

Conductivity measurements enable the rate of hydrolysis of ureaby the enzyme urease to be determined. The addition of an ap-propriate inhibitor poisons the enzyme, so that it no longer con-verts substrate.

Enzyme inhibition (poisoning of enzymes) (with Cobra4)Enzyme inhibition (poisoning of enzymes) (with Cobra4)


P4120660P4120660

PrinciplePrinciple

Catalase is an enzyme that - in humans - is found predominantlyin the liver and erythrocytes. It decomposes hydrogen peroxide,which is a toxic byproduct of cellular respiration, into water andoxygen.

TasksTasks

1. To examine the enzymatic decomposition of hydrogenperoxide, a cell respiratory poison, in the liver.

2. To investigate the influence of the temperature and pHon the metabolic activity.

The enzymatic activity of catalase (with Cobra4)The enzymatic activity of catalase (with Cobra4)




187

PrinciplePrinciple

As a result of the need to save energy and the increased con-sciousness of environmental problems, biotechnological produc-tion methods are on the advance. Fermenters are used for thebiotechnological production of enzymes and other products usingbacteria, yeast and cell cultures. For educational purposes abubble bioreactor used in this experiment is a more convenientand economical alternative to commercial fermenters. To demon-strate how fermenters work, in this experiment molasse which isa waste product of sugar production is fermented in the so-calledbatch process.

TasksTasks

1. Molasse is to be fermented to ethanol.2. Determine the yield of your process.


▪ Fermentation▪ Ethanol▪ Bioreactor▪ Yeast




Bubble bioreactor 65999-00 1




Liebig Condenser, with head, GL18/8 35795-15 1

Bubble bioreactorBubble bioreactor


This consists of a long glass tube jacket for temperature controland a glass insert tube which reaches from tip to tip. The jackethas two hose nipples for entry and exit of the temperature con-trolling liquid. The GL 32/18 opening in the bottom of the reactoris for aeration, the two openings at the top (GL25/8 and GL 18/8)are for the addition of the culture medium or for removal offinalproducts.


▪ Length: 400 mm; Diameter: 50 mm

65999-0065999-00

P1313600P1313600 Fermentation of molasse to ethanol with yeastFermentation of molasse to ethanol with yeast

Destillation of the fermented mash.

10 Biochemistry and Biotechnology10 Biochemistry and Biotechnology10.2 Biotechnology


188

PrinciplePrinciple

The properties of the microorganism Zymomonas mobilis havebeen used in the production of alcohol for centuries. Nevertheless,the bacterium in palm wine and pulque, the fermented juice ofthe agave plant, was not identified and recognised as being re-sponsible for their alcoholic fermentation until the twentieth cen-tury. Zymomonas was found to synthesise ethanol much more ef-fectively than yeast does.

In this experiment, Zymomonas mobilis is grown in a bioreactor.The medium is blended by means of a magnetic stirrer and itstemperature is controlled by means of a heating coil and a waterbath with thermostats. The discharge of used medium and thesupply of fresh medium can be dispensed with. This is a so-called'static culture' (batch culture).

The cell density can first be determined photometrically in thesamples taken and the cell count can be determined in the count-ing chamber, and those data can be used to generate a growthcurve. Chemical and enzymatic tests show the consumption ofglucose and the production of ethanol.

The experiment is easy to perform. It does not take long to pre-pare.

The evaluation of the test results is very conclusive and clearly il-lustrates the methods of biotechnology.

TasksTasks

1. Prepare the agar plates that are to be used for strain main-tenance of the bacteria to be used.

2. Determine the course of the fermentation of Zymomonas bya turbidimetric procedure.

3. Determine the cell count microscopically in a haemocytomet-er.


▪ Turbidimetry▪ Zymomonas mobilis▪ Cell count▪ Haemocytometer▪ Yeast▪ Fermentation


Spectrophotometer S800, 330...800 nm 35600-99 1

Autoclave with insert 04431-93 1

Drying oven UNB200, timer,32 l 46959-93 1

Centrifuge w. angle rotor 8x15 ml 65973-93 1


Set of Precision Balance Sartorius TE 412 andmeasure software balances,230 V 48835-88 1

Bioreactor, 1 l, 7 connections 66000-00 1

P1313762P1313762Microbial synthesis of ethanol by Zymomonas mobilis subsp.Microbial synthesis of ethanol by Zymomonas mobilis subsp.mobilis (with Cobra4)mobilis (with Cobra4)

Enzymatic processes (Entner-Doudoroff path-way).



189

PrinicplePrinicple

A bacteria culture of Corynebacterium glutamicum is used in abioreactor at a constant temperature of 30 °C to produce aminoacids. Under these conditions the fermentation of Corynebacteri-um glutamicum takes place in a so-called batch process for 7 to10 days.

TasksTasks

1. Start the fermentation of Corynebacterium glutamicum.2. Determine the yield of the process.3. Determine the composition of the mixture of amino acids us-

ing TLC.


▪ Fermentation▪ Thin layer chromatography▪ Amino acids





Bioreactor, 1 l, 7 connections 66000-00 1




Autoclave with insertAutoclave with insert


Portable autoclave with insert.


▪ With precision manometer▪ Thermometer▪ Integrated heating▪ Application range up to 1.4 bar at 125 °C or up to 2.7 bar at

140 °C▪ Volume: 12 liters; safety valve▪ Excess pressure safetyvalve; safety lock

04431-9304431-93

P1313862P1313862 Production of amino acids by fermentation of CorynebacteriumProduction of amino acids by fermentation of Corynebacteriumglutamicum (with Cobra4)glutamicum (with Cobra4)

Preparation of the strain maintenance plate.



190

PrinciplePrinciple

Scientists first recognised importance of certain bacteria for theextraction of metals from ore in the 1950s. Nowadays the micro-bial ore leaching with so-called 'lean ores' represents more than10% of the total production of copper in the USA alone. The biore-actor shown here can be used to clearly demonstrate to the stu-dents this method of extraction (e.g. copper from copper ore) us-ing such bacteria (Thiobacillus ferrooxidans).






Bubble bioreactor 65999-00 1



Cobra4 Mobile-Link set, incl. rechargeableCobra4 Mobile-Link set, incl. rechargeablebatteries, SD memory card, USB cable andbatteries, SD memory card, USB cable andsoftware "measure"software "measure"


The Cobra4 Mobile-Link is a modern, high performance handmeasuring device for mobile data recording, to which all Cobra4Sensor-Units can be connected via secure plug-in/ lockable con-nection.

12620-5512620-55

P1313962P1313962Bacteria and mining - microbial extraction of ore by ThiobacillusBacteria and mining - microbial extraction of ore by Thiobacillusferrooxidians and thiooxidans (with Cobra4)ferrooxidians and thiooxidans (with Cobra4)

Chemical process during extraction.



191

PrinciplePrinciple

As early as 1864, Louis Pasteur recognised that both alcoholic fer-mentation and the oxidation of alcohol to acetic acid dependupon the metabolic performance of specific bacteria. Gram-neg-ative, flagellated rods are responsible for the formation of aceticacid. Two large groups are differentiated here, the representativesof one of these are comprised of the genus Acetobacter, and thoseof the other of the genus Gluconobacter. In nature, these bacteriaare to be found on fruit, in floral nectar and leaf nectar, as well asin beer, wine and fruit juices. They are capable of utilising simplesugar as well as simple alcohol as substrate.

TasksTasks

1. Determine the ethanol content by an enzymatic indicator re-action.

2. Determine content of acetic acid by an enzymatic indicatorreaction.

3. Produce acetic acid with the "rapid vinegar procedure".


▪ "Rapid vinegar procedure"▪ Acetic acid▪ Immobilised cells▪ Bacterial culture


Spectrophotometer S800, 330...800 nm 35600-99 1


Drying oven UNB200, timer,32 l 46959-93 1

Centrifuge w. angle rotor 8x15 ml 65973-93 1

Peristaltic pump, 220V, 8 to 60 ml/min. 35705-93 1



Drying oven UNB200, timer, 32 lDrying oven UNB200, timer, 32 l


Drying oven UNB200 for drying, sterilizing, warming and incubat-ing in the temperature range from30 °C to 220 °C.

46959-9346959-93

P1314000P1314000 Immobilised cells in the service of biotechnology - microbialImmobilised cells in the service of biotechnology - microbialsynthesis of acetic acid with Acetobacter acetisynthesis of acetic acid with Acetobacter aceti

The biochemical oxidation of alcohol.



192

Complete Experiments Chemistry/Complete Experiments Chemistry/BiotechnologyBiotechnology


Complete Experiments Chemistry and BiotechnologyThis documentation contains the following experiments:This documentation contains the following experiments:

Model experiment on the fractional distillation of petroleumP1308600P1308600

Reaction of aldehydes with ammoniaP1308700P1308700

Determination of molar masses with the vapour density methodP1308800P1308800

Distillation - determination of the alcohol content of wineP1308900P1308900

Determination of enthalpies of combustionP1309000P1309000

Synthesis of ethyl acetate and butyl acetateP1309100P1309100

Electrostatic flue gas cleaningP1309200P1309200

Column chromatography - separation of leaf pigmentsP1309300P1309300

Determination of the molar masses of metalsP1309400P1309400

Faraday's lawsP1309500P1309500

Avogadro's lawP1309600P1309600

Air analysis (nitrogen in air)P1309700P1309700

E.M.F. measurements with a standard hydrogen electrodeP1309800P1309800

Obtaining vegetable oils by extractionP1309900P1309900

Model experiment on the desulphurisation of flue gasP1310000P1310000

Chemical fountainP1310100P1310100

Boiling point elevationP1310200P1310200

Gas lawsP1310300P1310300

The contact processP1310400P1310400

Molten-salt electrolysisP1310500P1310500

Steam distillationP1311500P1311500

PEM fuel cellP1312000P1312000

Synthesis of waterP1312100P1312100

Fermentation of molasse to ethanol with yeastP1313600P1313600

Microbial synthesis of ethanol by Zymomonas mobilis subsp.mobilisP1313700P1313700

Production of amino acids by fermentation of CorynebacteriumglutamicumP1313800P1313800

Bacteria and mining - microbial extraction of ore by Thiobacillusferrooxidians and thiooxidansP1313900P1313900

Immobilised cells in the service of biotechnology - microbialsynthesis of acetic acid with Acetobacter acetiP1314000P1314000

01855-0201855-02

MicrobialMicrobial synthesissynthesis ofof ethanolethanol byby ZymomonasZymomonas mobilismobilis subsp.subsp.mobilis - P1313700mobilis - P1313700

10 Biochemistry and Biotechnology10 Biochemistry and Biotechnology10.3 Literature


193

Demo advanced Biology Manual Cobra4Demo advanced Biology Manual Cobra4Biochemistry & plant physiologyBiochemistry & plant physiology



Experimental descriptions from the fields of biochemistry andplant physiology that pay particular attention to the advantagesof data acquisition with the Cobra4 system. In total more than 10demonstration experiments are described in detail.

TopicsTopics

▪ Photosynthesis (2 different methods)▪ Transpiration of leaves▪ Glycolysis (2 different methods)▪ The ionic permeability of the cell membrane▪ Determination of the Michaelis constant▪ Enzyme inhibition▪ Substrate inhibition of enzymes▪ The enzymatic activity of catalase


Din A4 stapled, in colour

56 pages


Transpiration of leaves (with Cobra4)P1351260P1351260

Photosynthesis (O2 pressure measurement) (with Cobra4)P1351360P1351360

Glycolysis (temperature measurement) (with Cobra4)P1351460P1351460

The enzymatic activity of catalase (with Cobra4)P1360760P1360760

Photosynthesis (bubble-counting-method) (with Cobra4)P1360860P1360860

Glycolysis (pressure measurement) (with Cobra4)P1360960P1360960

Ionic permeability of the cell membrane (with Cobra4)P1369760P1369760

Determination of the Michaelis constant (with Cobra4)P1369860P1369860


01331-0201331-02

Glycolysis - P1351460Glycolysis - P1351460

Enzyme inhibition - P4120560Enzyme inhibition - P4120560

Photosynthesis (bubble-counting-method) - P1360860Photosynthesis (bubble-counting-method) - P1360860

10 Biochemistry and Biotechnology10 Biochemistry and Biotechnology10.3 Literature


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About PHYWEAbout PHYWE11.111.1 Company profileCompany profile11.211.2 Nobel Prize ExperimentsNobel Prize Experiments11.311.3 Computer Assisted MeasurementComputer Assisted Measurement11.411.4 Safety InstructionsSafety Instructions11.511.5 General terms and conditionsGeneral terms and conditions

11 About PHYWE11 About PHYWE


195

11 About PHYWE11 About PHYWE11.1 Company profile


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11 About PHYWE11 About PHYWE11.1 Company profile


197

11 About PHYWE11 About PHYWE11.2 Nobel Prize Experiments


198

11 About PHYWE11 About PHYWE11.2 Nobel Prize Experiments


199

11 About PHYWE11 About PHYWE11.3 Computer Assisted Measurement


200



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207

11 About PHYWE11 About PHYWE11.5 General terms and conditions


208

210210212212216216

IndicesIndices12.112.1 Numerical IndexNumerical Index12.212.2 Alphabetical IndexAlphabetical Index12.312.3 www.PHYWE.comwww.PHYWE.com

12 Indices12 Indices


209

Art no.Art no. DescriptionDescription PagePageP1025200 Oxidation of metals 135P1026800 Reduction of silver oxide 136P1026900 Reduction of copper oxide 136P1135700 Osmosis - dependence of the osmotic… 32P1268360 Voltage of a concentration cell (with Cobra4) 116P1273460 Heat of fusion of sodium thiosulphate… 120P1282360 Electrochemical series of metals (with… 116P1308962 Distillation - determination of the… 162P1309200 Electrostatic flue gas cleaning 175P1309400 Determination of the molar masses of metals 23, 44P1310000 Model experiment on the desulphurisation… 174P1310100 Chemical fountain 26P1310500 Molten-salt electrolysis 135, 173P1313600 Fermentation of molasse to ethanol with yeast 188P1313762 Microbial synthesis of ethanol by… 189P1313862 Production of amino acids by fermentation… 190P1313962 Bacteria and mining - microbial… 191P1314000 Immobilised cells in the service of… 192P2140300 Viscosity of Newtonian and non-Newtonian… 77P2140400 Viscosity measurement with the falling… 78P2210300 Dispersion and resolving power of a prism… 132P2310100 Thermal expansion in solids and liquids 91P2320201 Heat capacity of gases 81P2320300 Maxwellian velocity distribution 75P2320400 Thermal equation of state and critical point 73P2411100 Characteristic curve and efficiency of a… 114P2510200 Specific charge of the electron e/m 128P2510311 Franck-Hertz experiment with a Hg-tube 125P2510315 Franck-Hertz experiment with a Ne-tube 125P2510600 Fine structure: One and two electron spectra 126P2510700 Balmer series/ determination of… 127P2511006 Zeeman effect with a variable magnetic system 129P2511111 Stern-Gerlach experiment with a step… 130P2511205 Model experiment NMR / ESR 64P2532000 Atomic Resolution of the graphite… 148P2538000 Basic methods in imaging of micro and… 150P2538400 Imaging of biological and medical micro… 150P2541301 Examination of the structure of NaCl… 143P2541401 X-ray investigation of cubic crystal… 144P2541501 X-ray investigation of hexagonal crystal… 144P2541601 X-ray investigation of crystal structures… 145P2541602 X-ray investigation of crystal structures… 145P2542101 Debye-Scherrer diffraction patterns of… 146P2542201 Debye-Scherrer diffractions pattern of… 146, 147P2542301 Debye-Scherrer diffraction patterns of… 146P2542401 Debye-Scherrer diffraction patterns of… 146P2542501 Debye-Scherrer diffraction patterns with… 146P2544501 Qualitative X-ray fluorescence… 58P2544601 Qualitative X-ray fluorescence analysis… 58P2544701 Qualitative X-ray fluorescence analysis… 56P2545001 Quantitative X-ray fluorescence analysis… 57P2545101 Quantitative X-ray fluorescence analysis… 58P3010301 Diffusion in gases: The diffusion… 76P3010401 Determination of molar mass using the… 19P3010501 Determination of the molecular mass of a… 20P3010601 Determining the molecular weight of a… 79P3011160 Gay-Lussac's law (with Cobra4) 70P3011260 Amontons' law (with Cobra4) 71P3011360 Boyle's law (with Cobra4) 72P3011400 Condensation of gases through an increase… 122P3020260 Adiabatic coefficient of gases -… 80P3020411 Determination of the enthalpy of… 82P3020460 Determination of the enthalpy of… 82P3020501 Partial molar volumes 83P3020611 Determination of the mixing enthalpy of… 84P3020660 Determination of the mixing enthalpy of… 84P3020711 Determination of the hydration enthalpy… 85P3020760 Determination of the hydration enthalpy… 85P3020811 Determination of the enthalpy of… 25, 85P3020860 Determination of the enthalpy of… 25P3020911 Determination of the melting enthalpy of… 86P3020960 Determination of the melting enthalpy of… 86P3021001 Boiling point elevation 117P3021101 Freezing point depression 118P3021401 Determination of the enthalpy of… 87P3021501 Determination of the heat of formation of… 88P3021601 Determination of the heat of formation… 89P3021701 Determination of the heating value of… 90, 179P3021900 Determination of molar masses via a… 21P3022000 Determination of molar masses via a… 22P3030401 Boiling point diagram of a binary mixture 119P3030501 Solubility diagram of two partially… 28P3030601 Miscibility gap in a ternary system 29P3030701 Distribution equilibrium 18P3030862 Solubility product (with Cobra4) 33P3030960 Dissociation equilibrium (with Cobra4) 17, 34P3031001 Complex formation equilibrium / complex… 16, 137P3031101 Dissociation constants 35P3031251 Steam distillation 124, 161P3031360 Melting diagram of a binary mixture (with… 121P3031401 Law of integer ratio of volumes according… 73P3031501 Rectification - the number of… 160, 177P3031640 Fractional distillation with the bubble… 124, 160P3031660 Fractional distillation with the bubble… 176P3031760 Chromatographic separation processes: Gas… 53P3031900 Sublimation and solubility of iodine 123

Art no.Art no. DescriptionDescription PagePageP3040801 Adsorption isotherms 92P3050101 Saponification rate of tert-butyl chloride 93P3050201 Reaction rate and activation energy of… 95P3050301 Kinetics of the inversion of saccharose 96P3050760 Halogen exchange rate (with Cobra4) 97P3050860 Conductometric measurement of the… 98P3051101 Dependence of the reaction velocity on… 94P3060111 Charge transport in solids (with Cobra3) 101P3060160 Charge transport in solids (with Cobra4) 101P3060260 Charge transport in liquids (with Cobra4) 102P3060301 Ion migration velocity 103P3060401 Transference numbers 104P3060560 Temperature dependence of conductivity… 105P3060660 Conductivity of strong and weak… 106P3060760 Conductivity titration (with Cobra4) 46P3060862 Determination of the activity coefficient… 107P3060962 Nernst equation (with Cobra4) 108P3061062 Concentration cells without transport:… 31P3061101 Determination of diffusion potentials 32, 109P3061262 Temperature dependence of the… 110P3061460 Precipitation titration (with Cobra4) 49P3061562 pH measurement (with Cobra4) 111P3061660 Titration curves and buffering capacity… 24, 50P3061760 Potentiometric pH titration (phosphoric… 47P3061811 Electrode kinetics: The hydrogen… 112P3061860 Electrode kinetics: The hydrogen… 112P3062101 Determination of Faraday's constant 113P3062201 Electrogravimetric determination of copper 51, 115P3070101 Absorption of light (UV-VIS spectroscopy) 66P3070301 Excitation of molecules 66P3070401 Absorption spectra and pKa values of… 66P3100100 Effects of acids on metals 135P3100300 Reduction - reducing agents - redox process 38P3100400 Reduction of lead oxide 39, 136P3101000 Haloalkanes: Grignard reagent 138P3101100 Haloalkanes: Wurtz reaction - lithium… 139, 154P3101300 Toluene: Bromination in the nucleus 155P3101400 Aldehydes - reactions with ammonia 156P3101500 Preparation of p-toluenesulfonic acid 157P3101600 Cannizzaro reaction and reaction of… 158P3110100 Obtaining nitrogen oxides by burning air 168P3110200 Ammonia preparation from the elements… 169P3110300 Combustion of ammonia to produce nitrogen… 170P3110400 Sulphur trioxide - the sulphuric acid… 171P3110500 Preparation of iron from oxidic ores… 182P3110600 Redox reactions between metals and metal… 37, 134P3110700 Salts of sulphuric acid - sulphates 172P3110800 Cracking of hydrocarbons 178P3110900 The empirical formula of methane, ethane… 41P3111000 Avogadro's law 42P3120100 Separation of mixtures of liquids and of… 163P3120200 Quantitative determination of fat /… 164P3120300 Column chromatography - separation of… 54P3120400 Chromatographic separation processes:… 52P3120500 Electrophilic addition of bromine to… 159P3121060 Volumetric redox titration: Cerimetry… 48P3121260 Titration of a polyvalent acid with a… 27, 50P3121360 Titration of a weak organic acid with… 27, 50P3121460 Titration of a weak base (ammonia) with a… 27, 50P3121660 Briggs-Rauscher Reaction (with Cobra4) 43, 99P4100760 The origin of acid rain (with Cobra4) 30P4120160 Determination of the isoelectric point of… 184P4120360 Determination of the Michaelis constant… 185P4120460 Substrate inhibition of enzymes (with Cobra4) 186P4120560 Enzyme inhibition (poisoning of enzymes)… 100P4120660 The enzymatic activity of catalase (with… 187P5510100 Metallographic sample preparation -… 180P5510200 Metallographic sample preparation -… 181P5942100 Fundamental principles of Nuclear… 62, 131P5942200 Relaxation times in Nuclear Magnetic… 6301196-12 Handbook Glass Jacket System 7401200-02 Handbook Physics X-Ray Experiments 15201233-02 Laboratory Experiments Magnetic Resonace… 6301331-02 Demo advanced Biology Manual Cobra4… 19401837-02 TESS Chemistry manual Organic Chemistry 16601855-02 Complete Experiments Chemistry/Biotechnology 19302611-00 Plunger eudiometer 4202612-00 Slow eudiometer 4102615-00 Glass jacket 8802615-01 Calorimeter insert for glass jacket 9002740-95 Rotary vane pump, one stage, 115 V/230 V 1904233-00 Dilatometer with clock gauge 9104403-00 Calorimetric bomb 8704431-93 Autoclave with insert 19006605-00 Flat chamber for ionic migration 10306748-00 PEM electrolyser 11406959-01 e/m - Observation chamber 12807128-00 Digital multimeter 2010 11507157-93 Large-scale display, digital, RS-232 port 16208173-00 Gas liquefier 12208493-93 Immersion thermostat Alpha A, 230 V 8309058-30 XR 4.0 X-ray energy detector (XRED) 5709060-00 Kinetic gas theory apparatus 7509110-88 XRE 4.0 X-ray expert set 56, 5709140-88 XRS 4.0 X-ray structural analysis upgrade set 143, 14409160-88 XRM 4.0 X-ray material analysis upgrade set 56, 57

12 Indices12 Indices12.1 Numerical Index


210

Art no.Art no. DescriptionDescription PagePage09180-88 XRCT 4.0 X-ray Computed Tomography… 14509500-99 Compact MRT 5909600-99 Compact-Scanning Tunneling Microscope (STM) 14909613-00 Set samples nanomorphology, for Compact… 14909700-99 Compact-Atomic Force Microscope (AFM) 15111207-20 Light barrier, compact 8012600-00 Cobra4 Wireless Manager 34, 4312601-00 Cobra4 Wireless-Link 30, 10212602-00 Cobra4 Remote-Link 7112620-55 Cobra4 Mobile-Link set, incl.… 19112630-00 Cobra4 Sensor-Unit Chemistry, pH and 2 x… 49, 9912632-00 Cobra4 Sensor-Unit Conductivity+,… 33, 9712636-00 Cobra4 Sensor-Unit Drop Counter 17, 2412736-00 Cobra4 hand-held pressure and temperature… 23, 4413300-10 TESS advanced General Chemistry,… 1313301-10 TESS advanced Inorganic Chemistry,… 1413431-88 TESS advanced General Chemistry,… 1313433-88 TESS advanced Inorganic Chemistry,… 1413500-93 Power supply, universal 51, 10113531-93 Variable transformer, 25 VAC/ 20 VDC, 12 A 6413601-99 Universal Counter 8113617-93 Temperature meter digital, 4-2 11713670-93 High voltage supply unit, 0-10 kV 73, 17513701-01 Conductivity temperature probe Pt1000 46, 10713715-93 Work and power meter 8213727-99 Multi channel analyser 5614550-61 Software Cobra4 - multi-user licence 48, 12015300-88 TESS advanced Chemistry set General… 1315301-88 TESS advanced Chemistry set Inorganic… 1418220-00 Falling ball viscometer 7818223-99 Rotary viscometer, 15 - 2,000,000 mPas,… 7732246-93 Heating apparatus for glass jacket system 16135010-06 Separation chamber, 180x120x50 mm 5235610-88 Measurespec spectrometer with cuvette… 6535635-02 Spectrometer/goniometer with vernier 126, 13235655-93 Spectrophotometer 190-1100 nm 3535750-93 Magnetic stirrer MR Hei-Standard 9435790-15 Water separator GL25/12 15735809-15 Soxhlet attachment, GL25/12 16435821-00 Osmosis and electrochemistry chamber 10935854-15 Funnel for gas generator, 50 ml, GL18 17135900-02 Condenser, reflux, with 2 Gl connection 12335906-93 Half-shade polarimeter, 230 V AC 9635912-00 Abbe refractometer 119, 15835918-88 Set rectification plant, 230 V 160, 17736820-00 Apparatus for elevation of boiling point 2136821-00 Apparatus for freezing point depression 2239818-88 Molecular model constuction kit, polymer… 15439821-88 Molecular model construction kit, organic… 17839837-00 Molecular orbital models, organics 137, 15540014-00 Crystal-lattice model sodium chloride 17340018-00 Crystal-lattice model fluorite 13540022-00 Crystal-lattice model ice 11840461-00 Gasometer 1000 ml 89, 13940466-00 Gas bar 3843003-88 Set gas laws with glass jacket, 230 V 2043020-00 Set Gas laws with glass jacket system and… 7243030-88 Set calorimetry, 230 V 25, 8444518-00 Electrolysis apparatus-Hofmann 11345052-00 Manual centrifuge for 4 specimens 16345510-00 Panel for complete experimental setups 26, 17446959-93 Drying oven UNB200, timer, 32 l 19247310-02 Periodic system with colour pictures 2947334-93 Magnetic stirrer Mini / MST 10649224-88 Set of Precision Balance Sartorius CPA… 1665999-00 Bubble bioreactor 18870000-93 Grinding and polishing machine, 230 V… 180

12 Indices12 Indices12.1 Numerical Index


211

AAAbsorption of light 66Absorption of X-rays 57, 58Acetals 158Acetic acid 192Acetylene 159Acid 26, 94, 135Acid rain 30Acid-base titrations 111Acidic anions 184Acidification of soil and water 30Activation energy 95Activity 33Activity coefficient 24, 50, 119Adsorbent and adsorbate 92Adsorbent material 52AFM 150Air 168Air and other gases 14Alkali-organyls 139, 154Alternative techniques e.g. Loschmidt's method 76Alternative techniques e.g. osmosis 79Aluminium 37, 134, 182Aluminothermics 37, 134, 182Amino acids 190Ammonia 156, 170Ammonia preparation from the elements… 169Amontons' law 71Amphoteric electrolytes 24, 50Analyser 56, 57, 145Angular momentum 126Anthropogenic air pollution 30Argentometry 49Arrhenius equation 95Atomic beam 130Atomic Force Microscope 150Atomic Force Microscopy 150Atomic form factor 143, 144, 145Atomic nuclei with a magnetic moment 62, 131Atomic scattering factor 146, 147Auger effect 57, 58Average velocity 75Avogadro 42Avogadro's law 73Avogadro's number 113

BBBacteria 150Bacterial culture 192Bacterial leaching 191Basic cations 184Benzaldehyde 158Binary system 28, 121Binding energy 127Bioreactor 188Blast furnace process 157, 182Bloch 59Blood Cells 150Bodenstein principle 185Bohr magneton 129, 130Bohr model 58, 127, 129Boiling point 119Boiling point diagram 160, 177Boiling point elevation 21Boyle and Mariotte's law 72Boyle temperature 73Bragg equation 145, 146Bragg scattering 143, 144, 146, 147Bragg-Brentano Geometry 146, 147Bravais lattice 145, 146, 147Bremsstrahlung 56, 57, 58Briggs-Rauscher reaction 43, 99Bromination 155Bromine 155, 159Bubble bioreactor 191Bubble tray column 124, 160, 176, 177Buffer 27, 50Buffering capacity 24, 50Building material 14Butterfly Wing 150

CCCalorimetry 25, 82, 84, 85Cannizzaro reaction 158Capillary action 52Carbon monoxide 39, 42, 136Catalyst 178Cathode rays 128Ce(IV) sulphate 48Cell count 189Cell voltage 47, 49Centrifugation 163Cerimetry 48Characteristic X-radiation 56, 57, 58, 143Characteristic X-rays 146, 147Charge 113Charge transport 101, 102, 104

Charge transport in liquids 103Charles's (Amontons') law 71Chemical bonds 13Chemical equilibrium 16, 137Chemical formula 41Chemical potential 117, 118, 119Chemical reactions 13Chlorine 42, 135, 173Chlorophyll 54Chromatogram 53Chromatography 53Clausius-Clapeyron equation 82Coefficient of thermal expansion 70Coexisting phase 28Coherent and incoherent photon scattering 57Column chromatography 54Complex formation 16, 137Compounds 136Compton 56, 57, 143, 144Concentration 32Concentration cells with transport 32, 109Concentration cells without transport 31Concentration ratio 117, 118Condensation 122, 124, 160, 176Conductance 105Conductance and conductance measurements… 98Conductivity 102, 103, 107Conductivity measurement 100, 185Conductivity-time plot 186Conductometry 46, 97Constant-Height and Constant-Current-Mode 148Contact process 171Continuous and discontinuous distillation 124, 160, 176Corrosion 112Cracking 178Critical dissolution temperature 28Critical point 73Cryoscopic constant 22, 118Crystal classes 145Crystal lattices 144, 145, 146, 147Crystal structures 143Crystal systems 144, 145, 146, 147Crystallisation 120Cubic compressibility coefficient 72

DDDamage to forests 30Daniell cell 110Debye-Scherrer 143, 144, 146, 147Decadic molar extinction coefficient 66Decomposition of H2O2 187Decomposition voltage 114Degree of dissociation 117, 118Degree of freedom 81Dehalogenation 159Desulphurization 174Determination of molar masses according to the… 20Determination oft he solubility products 31Differential molar mixing enthalpy 84Diffraction image of a diffraction grating 127Diffraction spectrometer 126Diffractometry 143, 144Diffusion Potential 32, 109Directional quantization 130Dispersion 132Dissociation 33Dissociation constant and pKa value 17, 34, 35Dissociation equilibrium 17, 34Dissociation of water 24, 50Distillation 124, 155, 158, 161Distillation column 160, 177Distribution and extraction 18Doublets 126Ductility 180Dynamic and kinematic viscosity 78Dynamic Mode 150

EEEbullioscopic constant 21, 117Ebullioscopy 21Edge absorption 57Electric filter 175Electric potential 116Electrical conductance 46Electrochemical cells 108Electrochemical potential 110Electrochemical series of metals 116Electrode 116Electrode kinetics 112Electrode polarisation 51, 114, 115Electrode potential 49Electrode potentials and their concentration… 108Electrode reactions 110Electrode-electrolyte interface 112Electrodes of the 1st and 2nd type 49Electrolysis 51, 104, 114, 115Electrolysis coulometry 113Electrolyte 46

12 Indices12 Indices12.2 Alphabetical Index


212

Electrolyte solutions 102Electrolytic conductance 33Electrolytic resistance 105Electromotive force 31, 110Electron charge 128Electron collision 125Electron conductivity 101Electron excitation 66Electron excitation spectroscopy (UV-VIS… 66Electron in crossed fields 128Electron mass 128Electron spin 129, 130Electrophilic addition 159Electrostatic filter 175Elements 136Emulsion 163Energie dispersive measurement 56, 57, 145Energy detectors 58Energy dispersive 57Energy level 56, 57, 58, 126Energy quantum 125Energy term symbols 146Enthalpy 25, 84, 85Enthalpy of combustion 87, 90, 179Enthalpy of condensation 82Enthalpy of formation 87, 88, 89Enthalpy of neutralisation 25, 85Enthalpy of reaction 88, 89Enthalpy of sublimation 82, 86Enthalpy of vaporisation 82, 86Entropy of vaporisation 82Enzymatic activity 187Enzymatic hydrolysis of urea 100, 185Enzyme catalase 187Enzyme-substrate complex 185Enzymolysis of urea 186Equation of adiabatic change of state 80Equation of state 19, 73Equation of state for ideal gases 20, 81Equilibrium between phases 18Equilibrium constant 16, 137Equilibrium diagram 119Equilibrium spacing 91Equivalence (inflection) points 184Equivalent conductance at infinite dilution 105Equivalent conductivity 106, 107ESR 64Etching 181Ethanol 162, 188Eutectic mixture 121Exchange energy 126Excitation energy 125, 126Exergonic process 43, 99Exhaust gas filter 175

FFFabry-Perot interferometer 129Faraday's law 113, 114Faraday's laws of electrolysis 104Fat extraction 164Feedback loop 149, 150Fermentation 188, 189, 190Fertilizer 14Fick's laws of diffusion 76FID signal 63FID signal (Free Induction Decay) 62, 131Finkelstein reaction 97First and second order reaction rates (laws) 98First law of thermodynamics 81, 87, 88, 89First order reaction 94, 96Flammersfeld oscillator 80Flue gas 174Fluidity 78Fluorescence 56, 57, 143, 144Fluorescent yield 56, 57, 58Food analysis 164Food chemistry 164Formaldehyde urotropine 156Franck-Hertz experiment 125Freezing point depression 22Fuel cells 112Fundamental principles of thermodynamics 84Fundamentals of distillation 119Fusion enthalpy 120

GGG-factor 130Galvani voltage 47Galvanic cell 47Galvanic elements 114Gas chromatography 124, 159, 160, 176Gas laws 42, 122Gas volumetry 20Gas- Molecules 75Gaseous and aerosol emissions 30Gay-Lussac's law 70, 73Gay-Lussac's law of chemical volumes 73General equation of state for ideal gases 73, 113

Gibb's phase law 29Gibbs-Helmholtz equation 117, 118Gibbs' phase law 121Gibbs' phase rule 86Glas manufacture 14Glass electrode 24, 50, 111Goniometer 132Gravimetry 51, 115Grignard reagent 138Grinding 180Ground and excitation states of molecules 66Grüneisen equation 91Gypsum 172, 174Gypsum calcination 172Gyroscope 64

HHHaber-Bosch process 169Haemocytometer 189Half-cell 116Half-life 93Haloalkanes 138Halogen exchange rate 97Heat capacity 25, 81, 85, 86Heat of combustion 90, 179Heat of reaction 90, 179Henderson-Hasselbalch equation 17, 24, 27, 34Henry Freundlich and Langmuir adsorption isotherms 92Henry's / Dalton's law 160, 177Henry's law 117Hess' law 85, 89Hess' law of constant heat summation 87Hexagonal Structures 148Hexamethylenetetramine 156Hittorf numbers 104Human hair 150Hydrocarbons 178Hydrochloric acid 26Hydrogen 42, 135Hydrolysis 24, 50, 156Hypsochromic and bathochromic shifts 66

IIIdeal and non-ideal behaviour of gases and liquids 83Ideal and ordinary gases 19, 20Ideal gas law 23, 44, 70, 71Ideal gases 73Imaging methods 59Imaging of biological samples 150Imaging on the sub nanometer scale 148Immobilised cells 192Indicators 24, 50Influence of solvents 66Influence of temperature and pH 187Integral enthalpy of solution 85Integral molar mixing enthalpy 84Interaction potential 73Interference of electromagnetic waves 129Interionic action 107Internal friction 77Iodine 123Ion conductivity 46, 101Ion mobility 46, 103, 104, 105Ion solvation 85Ionic migration 102Iron 37, 38, 134, 157Iron(II) sulphate 48Irreversible processes 112Isobars 81Isochors and adiabatic changes of state 81Isoelectric point 24, 50, 184Isotherms 81

JJJablonski diagram and Förster cycle 66

KKKinetic theory of gases 75, 76Kinetics of the inversion of saccharose 96Kohlrausch's law 105, 106

LLLambert-Beer Law 18, 35, 66Larmor frequency 59Latent heat 86Lattice 143, 144Lattice energy 85Lattice potential 91Laue 143, 144, 145Lauterbur 59Law of constant proportions 73Law of mass action 17, 24, 34, 35Law of thermodynamics 82Layer-thickness 56, 57, 145Lead 38, 39, 136Leaf pigments 54Lennard-Jones-Potential 150Lewis acid 155



213

Light scattering 79Limestone 174Linear expansion 91Lineweaver-Burk plot 185Liquid 78Liquid junction and diffucison potentials 31Liquid-liquid extraction 163Lithium organyls 139, 154Local Density Of States (LDOS) 148Longitudinal and transverse magnetization 63Lorentz force 128Lyman-, Paschen-, Brackett and Pfund Series 127

MMMacromolecules 79Magnesium 94, 138Magnetic field 64Magnetic induction 64Magnetic moment 130Magnetic Resonance Technology 63Magnetisation 59, 62, 131Mansfield 59Mark-Houwink equation 79Mass average and number average molecular weights 79Matrix effects 57, 58Maxwell relationship 132Maxwellian velocity distribution 75, 130Medical diagnostic 59Melt 121, 135, 173Melting 120Melting point 86, 121Melting point diagram 121Metal microscopy 181Metallographic phases 181Metallographic preparation 180Metals 14, 37, 134, 135Michaelis constant 185Micro distillation 158Microbial extraction 191Microbial synthesis of ethanol 189Micrography 181Miller indices 143, 144, 145, 146Miscibility gap 28, 29, 121Miscible liquids 28Mixed crystal 121Mixed phase 28Mixtures 13Mobile phase 52Model kinetic energy 75Model of electrons in a unidimensional potential box 66Molar and partial molar quantities 83Molar mass 21, 22, 23, 44Molar mass and relative molar mass 19Molar volume 23, 44Mole volumes 81Molecularity of reaction 93Molecule radius 73Monochromatisation of X-rays 146, 147Moseley's law 58Motor piston burette 184MR flip angle 62, 63, 131MR frequency 62, 63, 131MR physics 59, 62, 63, 131MRI 59MRT 59Multi channel analyser 56, 57, 58, 145Multiplicative distribution 53Multiplicity 126

NNn-propyl bromide 138Nano imaging 150Nanomorphology 149Nanotechnology 149Nernst distribution equation 18Nernst equation 32, 47, 49, 108Nernst's law of distribution (number of… 53Neutralisation 27, 50Newtonian liquid 77, 78Nitric acid 168, 170Nitrogen dioxide 168, 170Nitrogen monoxide 168, 170Nitrogen oxides 168NMR 59, 62, 64, 131Non-invasive 59Nuclear spins 59, 62, 63, 131

OOOptical rotation 96Ore 191Organometallic compounds 138, 139, 154Orthohelium 126Oscillating reactions 43, 99Osmosis 32Osmotic pressure 32Ostwald capillary viscometer 79Ostwald process 170Ostwald's law of dilution 105, 106

Overpotential 51, 112, 115Oxidation 38, 39, 42, 116Oxygen 42

PPParahelium 126Partial molar free enthalpy (chemical potential) 18Particle model 13PEM electrolyser 114PEM fuel cell 114pH indicators 111pH value 27, 50Phase diagram 29Phosphoric acid 27, 50Photometry 18, 35Piezo-electric devices 148pKa value 27, 50, 184Planck's constant 127Plasticity 77Poiseuilles's equation 79Poisoning of enzymes 100Poisonous by product of cell respiration 187Polarimetry 96Polarisability 132Polarisation 112Polarography 112Polishing 180Polytropic equation 80Polyvalent acid 27, 50Potential 43, 99Potentiometric determination of pH 111Potentiometry 17, 34, 47Powder diffractometry 143, 144Precession frequency 64Precession of nuclear spins 62, 63, 131Precipitation titration 49Pressure 70, 71, 72Principles of thermodynamics 18, 83Prism 132Production of iron 157, 182Properties of gases 19Properties of materials 13Proteolysis 27, 50Proton-Exchange-Membrane (PEM) 114Purcell 59

QQQualitative analysis 56, 57, 145Quantisation of energy levels 129Quantitative analysis 51, 56, 57, 115Quantum leap 125

RRRaoult's law 28, 117, 118, 119Rate law for first and second order reactions 93, 95, 97Reaction kinetics 94Reaction molecularity 98Reaction order 93, 98Reaction rate 93, 95, 96, 97Reaction rate constant 93, 95, 98Reaction velocity of enzymatic hydrolysis 186Reactions with pseudo order 95Real and ideal behaviour 84Real gases 73Reciprocal lattice 143, 144, 145, 146Rectification 124, 160, 176, 177Redox electrodes 108Redox reaction 37, 38, 39, 134Redox titration 48Reduction 38, 39, 42, 116Reflux ratio 160, 177Refractive index 132Relaxation times 62, 131Relaxation times T1/T2 59Relevance to electrolysis 112Resonance condition 62, 63, 131Resublimation 123Reveal crystallographic structure 181Rowland grating 132Rüchardt's experiment 80Rydberg frequency 58Rydberg's constant 127

SSSalt bridge 31Salt formation 135Saponification rate 93Scanning Tunneling Microscopy (STM) 148, 149Scattering of X-rays 58Screening constant 58Selection rules 126, 146Selectively permeable membrane 32, 109Self and mutual diffusion coefficients 76Semi-permeable membrane 32, 109Semiconductor 58Semiconductor energy detectors 56, 57, 58Separation of mixtures 13Separation procedure 52, 163



214

Shaking 163Shear stress 77Signal-to-noise ratio 62, 131Silver nitrate inhibition of urease 100Silver/silver nitrate half-cell 116Single crystal 143, 144Single electron atom 127Skin Cross-Section 150Slug 157, 182Sodium hydroxide 27, 50Sodium thiosulphate 120Solubility 26, 33, 58, 123Solubility product 49, 58Solution 116Solvatochromic 66Soxhlet apparatus 164Specific and molar conductivity 105Specific conductance 46Spectrometer 132Spectroscopical energy and adsorption measurement 66Spectroscopy 56, 57, 145Spin 126Spin echo 59, 62, 131Spin-lattice relaxation 63Spin-orbital angular momentum interaction 126Spin-spin relaxation 63SPM 149Starch-iodine solution 135, 173Static mode 150Stationary phase 52Steam distillation 124, 161Stern-Gerlach experiment 130STM 148, 149Stoichiometry 41, 122Stokes' law 78Strong and weak acids 17, 34, 35Strong and weak electrolytes 24, 50Structure amplitude 144, 145Structure analysis 143, 144Structure factor 143, 146, 147Sublimation 123Substituent effects 17, 34Substrate inhibition 186Sulphate 172Sulphur 174Sulphur trioxide 171Sulphuric acid 171, 172Supercooled melt 120Surface Chemistry 149Surface Physics 149

TTT1/T2 relaxation times 63Temperature 70, 71, 72, 75Temperature-dependence of conductivity 106Test reactions 13Thermal capacity 91Thermal capacity of gases 80Thermal conductivity detector 53Thermal expansion 91Thermal tension coefficient 71Thermite process 37, 134, 182Thermochemistry 88, 89Thermolysis 38Thin layer chromatography 52, 190Three component system 29Titration 48, 184Titration curves 24, 50Toluene 155Tomography 59Transference numbers 32, 104, 105, 109Transport properties 76Triangular diagram 29Trouton's rule 82True and potential electrolytes 17, 34, 35Tunneling effect 148Tunneling Effect 149Turbidimetry 189Two-wire field 130Types of electrodes 47

UUUniversal gas constant 70, 71, 72, 81UV-VIS spectrometry 35UV-VIS spectroscopy 66

VVVan der Waals equation 73Van't Hoff factor 118Vaporisation 124, 160, 176Vapour pressure 82, 124, 160, 176Velocity distribution 75Velocity gradient 77Vibration amplitude 150Vinegar procedure 192Viscosity 77, 105Viscosity measurements 78Viscosity of liquids 79

Visible spectral range 127Voltammetry and current-potential curves 112Volume 70, 71, 72Volume contraction 83Volume expansion of liquids 91Volumetry 46, 47, 92

WWWater - components of water and water purification 14Wave mechanics atomic model 66Welding of iron 37, 134, 182Wurtz synthesis 139, 154

XXX-ray 56, 57, 58, 143X-ray energy detector 56, 57, 145X-ray expert unit 56, 57, 143, 144X-ray fluorescence analysis 56, 57, 145X-ray upgrade set 56, 57, 143, 144Xanthophyll 54XRED 57

YYYeast 188, 189

ZZZeeman effect 129Zwitterions 184Zymomonas mobilis 189



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12 Indices12 Indices12.3 www.PHYWE.com


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