al chemistry syllabus

8/14/2019 AL Chemistry Syllabus

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F.6 Chemistry Teaching Schedule (2000-01)

Textbook: New Way Chemistry for Hong Kong A-level (Book1, 2 and 3)

Cycle Date Syllabus Explanatory Notes References in texts Remark 1. Atom, Molecules and

Stoichiometry1.1 The atomic structure

1.2 Radioactivity

1.3 Relative isotopic, atomic andmolecular masses

1.4 The mole concept

Protons, neutrons and electrons as constituents of the atom.

The relative masses and charges of a proton, neutron and electron.

The atomic nucleus. Relative size of the atom and atomic nucleus.

Nature of , particles, and ofradiation.

Equations for nuclear reactions.

Uses of isotopes in leak detection, radiotherapy, nuclear power and as

tracers. (Underlying principles and instrumentation are not required.)

A brief account of the mass spectrometer in determining relative

isotopic, atomic and molecular masses (instrumental details and

mathematical treatment of the mass spectrometer, and the use of

fragmentation in structure determination are not required.)

The mole and the Avogadro constant.

Molar volume of gases at R.T.P. (room temperature and pressure) and

S.T.P. (standard temperature and pressure). Ideal gas equation, pV=nRT

and its application to the relative molecular mass determination.

Chapter 1

Chapter 2

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1.5 The Faraday and the mole

1.6 Empirical and molecular formulae

1.7 Chemical equations and stoichiometry

(Non-ideal behaviour of real gases and kinetic theory are not required.)

Partial pressure of gas and its relationship to mole fraction.

The Faraday as the quantity of electricity of one mole of electrons.

Relationship between the mass liberated and the quantity of electricity

passed in electrolysis.

Derivation of empirical formula using combustion data or composition

by mass. Molecular formula derived from empirical formula and relative

molecular mass.

The stoichiometric relationship between reactants and products in a

reaction.

Calculation involving

i. reacting masses

ii. volumes of gases, and

iii. concentrations and volumes of solutions

Chapter 3

2. The Electronic Structure of Atoms

and the Periodic Table

2.1 Atomic emission spectra and

electronic structure of atomsCharacteristics of the emission spectrum of atomic hydrogen.

Interpretation of the spectrum using the relationship, E=hleading to the

idea of discrete energy levels.

Convergence limits and ionization. (Calculation are not required).

An awareness of the uniqueness of atomic emission spectra.

Chapter 4

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2.2 Electronic structure, ionization

enthalpies, electron shell

2.3 Atomic orbitals

2.4 Electronic configurations of atoms

Electronic configurations in relation to

Plots of the following graphs to introduce shells and sub-shells:

i. successive ionization enthalpies for a particular element, and

ii. first ionization enthalpies against atomic numbers (up to Z=20).

(Experimental determination of ionization enthalpy is not required).

An awareness of the wave nature of electrons, and that electrons are not

localized in fixed orbits. An atomic orbital as a representation of a region

within which there is a high probability of finding an electron. The

designation of s, p and d orbitals. The number and relative energies of

the s, p and d orbitals for the principal quantum numbers 1,2 and 3, and

also of 4s and 4p orbitals. Shapes of s and p orbitals only.

(The uncertainty principle is not required.)

Building up of electronic configurations based on three principles:i. electrons enter the orbitals in order of ascending energy

(Aufbau principle),

ii. orbitals of the same energy must be occupied singly before

pairing occurs (Hunds rule), and

iii. electrons occupying the same orbital must have opposite spins

(Paulis exclusion principle).

Electron configurations of isolated atoms from H to Kr.

Chapter 5

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the Periodic Table

2.5 The Periodic Table and the atomic

properties of the elements

Electron configurations of atoms represented by

i. Notation using 1s, 2s, 2p, etc., e.g. Fe (ground state)

1s22s2sp63s23p63d64s2

ii. electrons-in-boxes diagram

The Periodic Table, showing the s-, p-, d- and f-blocks. Interpretation of

the trends of ionization enthalpies and atomic radii of the elements in the

Periodic Table.

3. Energetics

3.1 Energy changes in chemical reactions

3.2 Standard enthalpy changes

3.3 Hesss law

Conservation of energy. Endothermic and exothermic reactions and their

relationship to the breaking and forming of bonds.

Enthalpy change, H, as heat change at constant pressure.

Standard enthalpy change of:

i. neutralization,

ii. solution,

iii. formation, and

iv. combustion

Experimental determination of enthalpy changes of reactions, limited to

simple calorimetric method. (Bomb carlorimeter is not required).

Use of Hesss law to determine enthalpy changes that are not easily

obtainable by experiment.

Enthalpy level diagrams.

Chapter 6

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Calculations involving enthalpy changes of reactions. Mid-term test

4. Bonding and Structure

4.1 The nature of forces holding atoms

together

4.2 Ionic bonding

Energetics of formation of ionic

compounds

Stoichiometry of ionic compounds

Ionic crystals

Electrostatic interactions between electrons and nuclei leading to

different types of bonding.

Formation of ions the tendency for atoms of elements in Groups I, II,

VI and VII to attain electronic configurations of noble gases.

Dot and cross diagrams for simple ionic compounds.

Born-Haber cycles for the formation of ionic compounds in terms of

enthalpy changes of atomization and ionization, electronic affinities and

lattice enthalpies.

(Electronic affinity is the enthalpy change when one mole of electrons is

added to one mole of atoms or ions in the gaseous state,

e.g. O(g) + e-O-(g) H = -141 kJ mol-1

O-(g) + e- O2-(g) H= +791 kJ mol-1;

Lattice enthalpy is the enthalpy change when one mole of an ionic

compound is formed from its constituent ions in the gaseous state,

e.g. Na+(g) + Cl-(g) NaCl(s) H = -781 kJ mol-1

Consideration in terms of electronic configurations and enthalpy changes

of formation.

Extended three-dimensional structures of ionic compounds limited to

Chapter 7

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Ionic radii

4.3 Covalent bonding

Dative covalent bonding

Bond enthalpies, bond lengths and

covalent radii

sodium chloride and caesium chloride. Unit cells and coordination

numbers.

(Calculations involving ionic radii in a unit cell are not required.)

Comparison of sizes of ions with their parent atoms.

Comparison of sizes of isoelectronic particles.

Formation of covalent bonding sharing of electron pairs.

The simple idea of the overlapping of atomic orbitals.

Dot and cross diagrams for simple molecules, e.g. CH4, NH3, H2O, HF.

Octet rule and its limitation, e.g. PCl5 and BF3.

Treated as a special example of covalent bonding, illustrated by

H3N->BF3. The simple idea of the overlapping of an empty orbital with

an orbital occupied by a lone pair of electrons.

Estimation of bond enthalpies using data from energetics.

Bond enthalpies as a comparison of the strength of covalent bonds.

Relationship between covalent bond enthalpies and bond lengths as

illustrated by hydrogen halides.

Addition of covalent radii to give approximate covalent bond lengths as

illustrated by simple molecules.

Chapter 8

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The shapes of covalent molecules

and polymeric ion

Multiple bonds

Covalent crystals

4.4 Bonding intermediate between ionic

and covalent

Incomplete electron transfer in ionic

compounds

Polarity of covalent bond

The shapes of simple molecules and polyatomic ions explained in terms

of the repulsion between electron pairs(as illustrated by BF3, CH4, H2O,

PCl5, SF6, NH4+ and NH2

-). The directional nature of covalent bonds.

Bond angles.

Comparison of bond lengths and bond enthalpies leading to the idea of

multiple bonds, illustrated by ethane and ethyne. Shapes of carbon

dioxide and sulphur dioxide molecules explained in terms of repulsion

between electron pairs.

Exemplified by diamond, graphite and quartz.

Comparison of the experimental lattice enthalpies of e.g. silver halides

and zinc sulphide, with the theoretical values calculated on a completely

ionic model leading to the idea of polarization of ions. (Calculation of

the theoretical value of lattice enthalpy is not required).

Displacement of an electron cloud leading to the formation of a polar

covalent bond. Dipole moment as evidence for bond polarization in

simple molecules. (Calculation of dipole moment is not required.)

Chapter 9

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4.5 Metallic bonding

Metallic crystals

4.6 Intermoleular forces

Van der Waals forces

Unequal sharing of bonded electron pair(s) explained in terms of the

electronegativity difference between bonded atoms.

Electronegativity (Paulings scale) introduced as an arbitrary measure of

an atoms tendency in a molecule to attract electrons. (The formal

definition of electronegativity and its experimental determination are not

required.)

Metallic bonding illustrated by a model of cationic lattice and mobile

valence electrons. Simple explanation of the metallic conduction of

electricity based on the model.

Strength of metallic bond in terms of metallic radii and the number of

valence electron(s) per atom.

Cross-packed and open structures: hexagonal and cubic close-packed,

and body-centred cubic structures. Unit cells and coordination numbers.(Calculations related to atomic radii in a unit cell are not required.)

Brief discussion of the origin of van der Waals forces in terms of

permanent, instantaneous and induced dipoles. Comparison of the

covalent and van der Waals radii of non-metals to indicate the relative

strength of the covalent bonds and van der Waals forces.

Chapter 10

Chapter 11

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Molecular crystals

Hydrogen bonding

4.7 The relationship between structures

and properties of materials

Exemplified by iodine and carbon dioxide.

A study of the boiling points and enthalpy changes of vaporization of the

hydrides of Groups IV, V, VI and VII and compounds like alcohols and

carboxylic acids leading to the idea of hydrogen bonding.

Nature of hydrogen bonding.

Relative strength of van der Waals forces and hydrogen bonding.

Hydrogen bonding in ice, proteins and DNA (deoxyribonucleic acid)

Differences in physical properties (viz. melting and boiling points,

electrical conductivity, hardness and solubility) between ionic

compounds, covalent substances and metals

Chapter 12

5. Chemical Kinetics

5.1 Rates of chemical reactions

5.2 Factors influencing reaction rate

5.3 Rate equations and order of reactions

The meaning of the rate of a chemical reaction.

Following a reaction by chemical and physical methods, viz. following

the change in amount of reactant/product by titration, determining the

volume of gas formed, or colorimetric measurement of light intensity at

different times. (The theory of colorimetry is not required.)

Effects of concentration, temperature, pressure, surface area, catalyst and

light on reaction rate.

Simple rate equations determined from experimental results.

Zeroth, first and second order reactions. Rate constants. Half-life of a

Chapter 13

Term examination

Chapter 14

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5.4 The effect of temperature change on

reaction rate

5.5 The interpretation of rates of gaseous

reactions at molecular level

5.6 Energy profile

first order reaction.

Radioactive decay as a typical example of a first order reaction.

Carbon-14 dating in the estimation of the age of an archaeological

specimen.

Cabon-14 dating in the estimation of the age of an archaeological

specimen.

Calculations involving rate equations. (Deriving of integral forms of rate

equations is not required.)

Explanation of the effect of temperature change on reaction rate in terms

of activation energy.

Application of the Arrhenius equation

k = A exp(-Ea/RT)

to determine the activation energy of a reaction. (Derivation of the

Arrhenius equation is not required.)

Distribution of molecular speeds in a gas. (Zartmann experiment and

calculations involving molecular speeds are not required.)

Graphical representation of the Maxwell-Boltzmann distribution and its

variation with temperature. Simple collision theory. (Qualitative

treatment only.)

Energy profile as a representation of the changes in potential energy

Chapter 15

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5.7 Catalysts and their effect on reaction

rates

Homogeneous and heterogeneous

catalysis

Applications of catalysts

during a reaction. Simple stage and multi-stage reactions.

The rate determining step in a multi-stage reaction.

Catalysts can change the rate of a reaction by providing an alternative

pathway for the reaction.

Acid-catalysed esterification as an example of homogeneous catalysis.

Effect of manganese(IV) oxide on the decomposition of hydrogen

peroxide as an example of heterogeneous catalysis.

The use of catalysts in Contact and Haber processes, and the

hydrogenation of unsaturated oils. Catalytic converters in c ar exhaust

systems. An awareness that enzymes are example of biological catalysts.

6. Chemical Equilibria

6.1 Dynamic equilibrium

The equilibrium law

The effect of changes in

concentration, pressure and

Reversible reactions.

Dynamic nature of chemical equilibrium.

Characteristics of chemical equilibrium.

Equilibrium constants expressed in terms of concentration (Kc) and

partial pressure (Kp). Simple calculations of Kc and Kp. (The quantitative

relationship between Kc and Kp is not required.)

Le Chateliers principle. Changes in concentration and pressure result in

the adjustment of the system without changing the value of equilibrium

Chapter 16

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temperature on equilibria

6.2 Acid-base equilibria

Concepts of acid/base

Dissociation of water

pH and its measurement

Strong and weak acids/bases

constant, K; a change in temperature results in the adjustment of the

system to a new equilibrium constant.

Reaction of temperature and the value of K for exothermic and

endothermic reactions illustrated by the equation,

ln K = constant H/RT

(Derivation of the equation is not required.)

Simple calculation on equilibrium composition involving changes in

concentration/pressure.

Bronsted-Lowry theory

Ionic product of water, Kw

The use of indicators and pH meters to measure pH. (The theory and

instrumentation of pH meters are not required.)

Dissociation constants for weak acids (Ka) and weak bases (Kb). Use of

Ka and Kb (pKa and pKb) values to compare the strength of weak acids or

weak bases. Calculations involving pH, Ka and Kb.

(For dissociation involving more than one step, calculations are limited

to one of these steps only.)

Chapter 17

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Buffers

Indicators

Acid-base titrations

6.3 Redox Equilibria

Redox reactions

Electrochemical cells

Electrode potentials

Principle of buffer action. Calculations involving the composition and

pH of buffer solutions.

Simple theory of acid-base indicators and pH range of their colour

changes.

pH titration curves and the choice of indicators.

Redox reactions in terms of electron transfer. Oxidation states. Balancing

redox equations.

E.m.f. measurement of electrochemical cells of metal-metal ion systems.

E.m.f. values to compare the relative tendencies of half cells to release or

gain electrons. Other systems involving non-metal ions.

(e.g. I2(aq) , 2I-(aq) | Pt), ions in different oxidation states(e.g. Fe3+(aq),

Fe2+(aq)|Pt) and metal-metal salt (e.g. PbSO(s), [Pb(s) + S O42-(aq)]|Pt).

Cell equations. IUPAC convention in writing cell diagrams.

The standard hydrogen electrode as a reference. The convention of

standard reduction potentials is adopted. The electrochemical series

(redox potential series). Use of the standard electrode potential (E)

values to compare the strength of oxidizing/reducing agents, and to

Chapter 18

Chapter 19

Chapter 20

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Secondary cell and fuel cell

Corrosion of iron and its prevention

calculate the e.m.f. of cells.

Prediction of the feasibility of redox reactions from electrode potential

values and the limitation of this approach due to kinetic factor.

Lead-acid accumulator and the hydrogen-oxygen fuel cell: structure,

electrochemical processes and uses.

The electrochemical process involved in rusting.

Prevention of corrosion by coating and cathodic protection.

Socioeconomic implication of corrosion and prevention.

7. Phase Equilibrium

7.1 One component systems

7.2 Two component systems

Ideal systems

Non-ideal systems

The pressure temperature diagrams of water and carbon dioxide.

(Phase rule is not required.)

Studies limited to phase diagrams for mixtures of two miscible liquids:

i. Vapour pressure against mole fraction (with temperature

constant), and

ii. Boiling point against mole fraction (with pressure constant).

Rauolts law. The characteristic properties of an ideal system explained

in terms of molecular interactions.

Positive and negative deviations from Rauolts law explained in terms of

molecular interactions. Enthalpy changes on mixing as evidence for non-

Chapter 21

Chapter 22

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Fractional distillation

7.3 Partition of a solute between two

phases

ideal behaviour. Azeotropic mixtures.

Explanation of the principle of fraction distillation using the boiling

point composition curve.

Application of fraction distillation in oil refining.

Partition coefficient of a non-volatile solute distributed between two

immiscible liquids. (Calculations involving dissociation or association of

solute are not required.) Application to solvent extraction.

Paper chromatography as an application of partition. Rfvalue.

Chapter 23

Term test

12. Fundamentals of OrganicChemistry

12.1 Natural sources of organic

compounds

12.2 The unique nature of carbon

12.3 Functional groups and homologous

series

Alkanes, alkenes and aromatic hydrocarbons from crude oil and coal.

Carbohydrates, proteins and fats in living organisms.

Ability of carbon to catenate leading to the existence of a vast number of

carbon compounds.

Studies limited to the following functional groups:

C=C, CC, -X, -OH, -O-, -CHO, C=O, -COOH, -NH2, -NHR, -NR2,

-CN, -COOR, -COX, -CONH2 and (-CO)2O.

Effects of functional groups and the length of carbon chains on physical

properties of compounds in homologous series.

Chapter 24

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12.4 Structures and shapes of

hydrocarbons

Saturated hydrocarbons

Unsaturated hydrocarbons

Aromatic hydrocarbons

12.5 Systematic nomenclature

12.6 Isomerism

Structural isomerism

Geometrical isomerism

The tetrahedral arrangement of the bond electron pairs around a carbon

atom explained in terms of repulsion between electron pairs and in terms

of sp3 hybridized orbitals. (Conformation is not required.)

Formation of the C=C and CC bonds explained in terms of sp2 and sp

hybridized orbitals respectively. andbonds. Shapes associated with sp2

and sp hybridized carbon atoms.

Shape of the benzene molecule.

Delocalization of -electrons in benzene giving rise to a unique class of

compounds which are chemically different from alkenes.

Systematic nomenclature limited to compounds containing carbon chains

of not more than eight carbon atoms.

Isomers containing the same functional group and isomers containing

different functional groups.

Rigidity of C=C bond leading to cis/trans isomers. Geometrical isomers

Chapter 25

Chapter 26

Chapter 27

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Enantiomerism

12.7 Structure determination of organic

compounds

Use of infra-red (IR) spectrum in the

identification of functional groups

limited to acyclic compounds containing one C=C.

Studies limited to structures with one chiral cabon.

(Absolute configuration and resolution of racemic mixtures are not

required.)

Calculation of empirical formula from analytical data (linked with

section 1.6). Molecular formula. Structure deduced from reactions of

functional groups and physical properties.

An awareness that spectroscopic methods such as infrared spectroscopy

and nuclear magnetic resonance (NMR) can provide information about

the structure of a molecule.

IR spectrum and its use in the identification of the following groups:

C-H, O-H, N-H, C=C, CC, C=O and CN. (Instrumentation is not

required.)

Chapter 28

13. Chemistry of Organic Compounds

13.1 Alkanes

Mechanisms other than those mentioned specifically are not required.

Crude oil as a source of alkanes.

Chemical principles and economic importance of fractional distillation

(linked with 7.2) and cracking process (Industrial detail are not

required.)

Combustion of alkanes. Chlorination of alkanes as light-initiated chain

Chapter 30

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13.2 Alkenes

Addition reactions

Ozonolysis

Polymerization of alkenes

13.3 Aromatic hydrocarbons

Substitution

reactions. Mechanism of the chlorination of methane.

Reactions of alkenes with bromine (aqueous and non-aqueous),

hydrogen bromide and sulphuric(VI) acid. Mechanism of the

electrophilic addition of hydrogen bromide to alkenes. Markownikoffs

rule.

Catalytic hydrogenation and its application in the hardening of oils.

Conditions and reaction products. Use in the determination of positions

of the carbon-carbon double bonds in alkenes.

Formation of poly(ethene), poly(propene) and poly(phenylethene).

Mechanism of free radical polymerization of ethane.

Benzene and methylbenzene.

Stability of the benzene ring: comparison of the enthalpy changes of

hydrogenation and combustion for benzene and cyclohexene leading to

the concept of increased stability in a delocalized system. Resistance of

benzene to oxidation and addition reactions.

Nitration, halogenation, sulphonation and alkylation. (limited to mono-

substitution only)

Reaction with potassium manganate(VII)

Chapter 31

Chapter 32

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Oxidation of alkylbenzene

13.4 Halogeno-compounds

Nucleophilic substitution reactions

Elimination reaction

Uses of halogeno-compounds

13.5 Hydroxy compounds

Acidic properties of hydroxy

compounds

Reactions of alcohols

Primary, secondary and tertiary haloalkanes, halobenzene.

Reactions with sodium hydroxide, potassium cyanide and ammonia.

(Experimentation involving potassium cyanide should not be attempted.)

Comparison of rates of hydrolysis of haloalkanes and halobenzene.

Mechanism of SN1 and SN2 as exemplified by substitution with OH

group. (Linked with 5.6)

Reaction of haloalkanes with alcoholic sodium hydroxide to form

alkenes and alkynes.

Halogeno-compounds as solvents in dry-cleaning and as raw materials in

the manufacture of poly(chloroethene) and poly(tetrafluoroethene).

Primary, secondary and tertiary alcohols; phenol.

Comparison of the acidic properties between alcohols and phenol.

Reactions include halide formation, alkoxide formation, oxidation,

dehydration, esterification and triiodomethane formation.

Chapter 33

Chapter 34

Term examination

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Reactions of phenol

Uses of alcohols

Distinction between primary, secondary and tertiary alcohols.

Reactions with sodium and sodium hydroxide.

Esterification.

Alcohols as solvents.

Ethanol in beverages and as a motor fuel blending agent.

Ethane-1.2-diol as an anti-freeze and a raw material in the manufacture

of terylene.

Cycle Date Syllabus Explanatory notes Reference in text Suggested ExperimentsCarbonyl compounds

Nucleophilic addition reactions

Addition- elimination (condensation) reactions

Structures of aldehydes and ketones. Benzaldehyde and phenylethanone as

aromatic carbonyl compounds.

Reactions with hydrogen cyanide and sodium hydrogensulphate( IV).

(Experimentation involving hydrogen cyanide should notbe attempted.)

Mechanism of the addition of hydrogen cyanid e to carbonyl compounds.

Use of the reaction with sodium hyd rogensulphate( IV) in the purification of

carbonyl compounds.

Reactions with hydroxylamine and 2, 4- dinitrophenylhydrazine.Identification of a carbonyl compoun

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Oxidation and reduction

Uses of carbonyl compounds

Oxidation of aldehydes with acidified dichromate( VI), Tollens' reagent and

Fehling's reagent. Resistance of ketones to oxidati on.

Reduction of aldehydes and ketones with sodium tetrahydridoborate (sodium

borohydride) and lithium tetrahydridoaluminate (lithium aluminium hydride).

Formation of triiodomethane as a test for compounds containing

a CH 3 CO group or a CH 3 CH( OH) group.

Methanal in the manufacture of urea- methanal resin.

Propanone as a solvent and a raw material in the manufacture of perspex.

preparing its derivative.

Investigation of the reactions of aldeh

ketones.

13.7

Carboxylic acids and their derivatives

The formation of carboxylic acid

Reactions of carboxylic acids

Acidity of carboxylic acids

Reactions of acyl chlorides and Anhydrides

Structures of carboxylic acids, acyl chlorides, anhydrides, amides and esters.

Hydrolysis of nitriles. Oxidation of alcohols, aldehydes and alkylbenzenes.

Formation of salts, acyl chlorides, anhydrides, amides and esters. Reduction with

lithium tetrahydridoaluminate.

Comparison of the acidity of carboxylic acids with alcohols.

Influence of substituents, viz. alkyl and chloro groups, on

acidity.

Reactions with water, alcohols, ammonia and amines.

Investigation of the reactions of carbo

acids.

Preparation of an ester.

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Reactions of amides

Reactions of esters

Uses of carboxylic acids and their derivatives

Nitrogen compounds

The formation of amines Primary amines from

nitriles and amides.

Base properties of amines

Reaction of amines

.

Hydrolysis, dehydration, Hofmann degradation and reduction with lithium

tetrahydridoaluminate.

Acid and base hydrolyses. Reduction with lithium tetrahydridoaluminate.

Benzoic acid and benzoates as food preservatives. Polyamides and polyesters as

synthetic fibres e. g. nylon 6. 6 and terylene.

Uses of esters as solvents and flavourings.

Primary, secondary and tertiary aliphatic amines, phenylamine and amino acids.

Primary, secondary and tertiary aliphatic amines, and quaternary ammonium

compounds by alkylation. Phenylamine from nitrobenzene.

Salt formation. Comparison of the basic strength of ammonia, primary aliphatic

amines and phenylamine.

Reactions with ethanoyl chloride and benzoyl chloride. Reaction with nitric( III)

acid limited to primary amines only. Coupling reaction of benzenediazonium ion

with naphthalen- 2- ol. (Test to distinguish primary, secondary and tertiary

amines is notrequired.)

Analysis of commercial aspirin tablet

Investigation of the reactions of amin

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Uses of amines and their derivatives

Amino acids

14. Chemistry and Society

14.1 Chemistry and the environment

(a) Air pollution

Some air pollutants

The effects of polluted air on the envi ronment

The ozone layer and chlorofluorocarbons

Azo- compounds as dyes in dyeing i ndustries. Amine derivatives as drugs.

Amino acids (e. g. aminoethanoic acid and 2- amino- propanoic acid) as

bifunctional compounds having both acidi c and basic characteristics. Zwitterion.

Dipeptides and polypeptides as dimers and polymers of amino acids. (Methods

of formation of polypeptides are notrequired.)

Carbon monoxide, sulphur dioxide, nitrogen oxides, hydrocarbons, ozone and

particulates. Combustion of fossil fuels as the main source of air pollutants.

The harmful effects of pollutants depend on their concentrations and the duration

of exposure to the pollutants. Parts per millio n (ppm) as one way of indicating

concentrations of pollutants. Acid rain and photochemical smog: their formation

and effects on the environment.

Sources and properties of ozone. The desirability of ozone in the stratosphere.

Chlorofluorocarbons as aerosol propellants, solvents for the cleaning of

Project work on air pollution, e.g. aci

smog or ozone depletion.

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(b) Water pollution

The causes of water pollution and its effects

on the environment

Water quality

(c) Solid waste

(d) Pollution control in Hong Kong

electronic components and metals, refrigerants, and blowing agents in foam

plastic manufacturing. Causes for the accumulation of chlorofluorocarbons in the

stratosphere. The free radical chain reactions involved with chloro-

fluorocarbons leading to the depletion of the ozone layer. Control of the ozone

depletion problem. Possible alternatives for chlorofluorocarbons.

The adverse effects on water quality due to liv estock waste, oil spillages,

residues of pesticide, detergents in sewage, and industrial effluents.

An awareness that oxygen dissolved in water is necessary for aquatic life.

Dissolved oxygen (DO) as an indicator of oxygen content in water, expressed as

percentage saturation or mg dm 3 . Biochemical oxygen demand (BOD) as an

indicator of the extent of water pollution.

Plastics, paper and metals. Disposal of solid waste b y landfilling and ncineration.

Pollution problems associated with the disposal of plastics. Development of

degradable plastics and recycling of plastics as possible solutions to pollution

problems.

Measures to improve air quality: use of unleaded petrol and installation of

catalytic converters in car exhaust systems, limitation of sulphur content in fuels,

Determination of dissolved oxygen in

samples.

Visit to

a. the Environment Resource Centr

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14.2 Chemistry and food

(a) Principal components of food Proteins

Carbohydrates

Fats and oils

desulphurization of flue gas, installation of electrostatic precipitators and

installation of low nitrogen oxide burners in power plants.

Measures to improve water quality: screening, sedimentation and digestion of

pollutants by micro- organisms in the treatment of sewage; ph ysical and

chemical methods, and incineration in the treatment of chemical waste from

industry and laboratories. (Technical details of the above treatment processes are

notrequired.)

Measures to reduce solid waste:

reuse/ recycling of paper, plastics and metals to minimize waste and save

resources.

Proteins as macromolecules made up of amino acids via peptide linkages.

Hydrolysis of proteins. Separation of amino acids by paper chromatography.

(Linked with Sections 7.3 and 13.8)

Classification into monosaccharide, disaccharide and polysaccharide. Open chain

and ring structures of glucose and fructose. Glycosidic linkage in carbohydrates.

Hydrolysis of sucrose and starch. Fehling's test to distinguish between reducing

and non- reducing sugars.

Fats and oils as esters of propane- 1, 2,3- triol and fatty acids. Hydrolysis of fats

and oils (Link with Section 13 .7). Use of iodine value tocomparethe degree of

b. the Chemical Waste Treatment C

c. a sewage treatment plant.

Separation of amino acids by paper

chromatography.

Investigation of the hydrolysis of suc

testing for reducing sugars.

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(b) Food preservation

The need to preserve food

Principles and techniques of food preservation

(c) Food additives

unsaturation. Hardening of vegetable oils. (Link with Section 13.2) Hydrolytic

and oxidative rancidity.

Prevention of food spoilage due to microbial activities and chemical changes.

Principles of food preservation:

killing of micro- organisms, inhibition of microbial growth, retardation of

chemical changes by removing moisture, altering temperature, changing pH, and

the use of osmotic process and chemical additives. Common techniques include

heat treatment, irradiation, drying, dehydration, refrigeration, canning, sugaring,

salting and chemical preservation such as meat- curing, picklin g and the use

of food additives.

Food additives to serve as preservatives (e. g. nit rates( III), nitrates( V), sulphur

dioxide, sulphates( IV), benzoic acid and b enzoates) and antioxidants (e. g.

BHA (butylated hydroxyanisole) and BHT (butylated hydroxytoluene)), to

enhance the flavour (e. g. MSG (monosodium glutamate), saccharin), texture

(e. g. emulsifying agents), appearance (e. g. colouring agent s) or nutritional

value (e. g. vitamins) of food.

Principle of BHA/ BHT as antioxidant to retard atmospheric oxidation of oils

and fats.

Investigation of the effects of air and

preservatives on apple browning.

Library search on different functions

common food additives.

Analysis of sulphur dioxide content in

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The possible menace of

food additives

8. Periodic Properties of the Elements in

the Periodic Table

8.1 Periodic variation in physical properties of

the elements H to Ar

8.2 Periodic relationship among the oxides,

chlorides and simple hydrides of the elements

Li to Cl

9. The s- Block Elements

9.1 Characteristic properties of the s- block

elements

The side effects of MSG, the toxicity of nitrates( III) and sulphur dioxide, and

the potent carcinogenic nature of nitrates( III) and saccharin.

An awareness that the use of food additives is monitored by research findings

and by legislation.

Variations in first ionization enthalpies (linked with Section 2. 2), atomic radii,

electronegativities and melting points. Interpretation of t hese variations in terms

of structure and bonding.

Bonding and stoichiometric composition of the hydrides, oxides and chlorides of

these elements, and their behaviour with water. (Hydrides of boron are not

required.)

Metallic character and low electronegativity. Formation of basic oxides and

hydroxides. Predominantly ionic bonding with fixed oxidation state in their

Debate on the use of food additives.

Investigation of the properties of the o

chlorides of the period 3 elements.

Flame tests for Li+, Na+, K+, Ca2+, Sr2

ions.

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9.2 Variation in properties of the s- block

elements and their compounds

9.3 Uses of the compounds of th e s- block

elements

10. The p- Block Elements

10.1 The halogens

Characteristic properties of the halogens

compounds. Characteristic flame colours of salts. Weak tendency to form

complexes.

Variations in atomic radii, ionization enthalpies, melting points and hydration

enthalpies. Interpretation of these variations in terms of structure and bonding.

Reactions of the elements with hydrogen, oxygen, chlorine and water.

Reactions of the oxides, hydrides and chlorides with water, acids and alkalis.

Relative thermal stability of the carbonates and hydroxides.

Relative solubility of the sulphates( VI) and hydroxides.

Sodium carbonate in the manufacture of glass.

Sodium hydrogencarbonate in baking powder. Sodium hydroxide in making

soap. Magnesium hydroxide as an antacid. Slaked lime in neutralization of acids

in industrial effluents. Strontium compounds in fireworks.

High electronegativity and electron affinity. Ionic and covalent bonding in

oxidation state 1.

Investigation of the effect of heat on c

of Group II elements.

Investigation of the solubility of sulph

and hydroxides of Group II elements

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Variation in properties of the halogens and

their compounds

Uses of halogens and halogen containing

compounds

10.2 Nitrogen and its compounds

10.3 Sulphur and its compounds

Variations in melting and boiling points, electronegativities and electron

affinities. Interpretation of these variations in terms of structure and bonding.

Relative oxidizing power of halogens: comparative study of reactions (Cl 2 ,

Br2 and I 2 ) with sodium, iron( II) ion and ph osphorus.

Disproportionation of the halogens in alkalis.

Comparative study of the reactions of halide ions with halogens, sulphuric( VI)

acid, phosphoric( V) acid and silver ions. Acidic properties of hydrogen halides

and the anomalous behaviour of hydrogen fluoride.

Fluoride in fluoridation of water. Chlorine in the manufacture of

poly( chloroethene), bleach and disinfectant. Silver bromide in photographic

films.

Unreactive nature of nitrogen. Direct combination of nitrogen and oxygen

leading to formation of nitrogen oxides. Manufacture of ammonia by Haber

process and its underlying physicochemical principles. Ammonia as a reducing

agent and a base. Catalytic oxidation of ammonia in the manufacture of

nitric( V) acid. Nitric( V) acid as an oxidizing agent, limited to the stud y of the

reactions with copper, iron( II) ion and sulphur only.

Action of heat on nitrates( V). Brown ring test for nitrate( V) ions.

Burning of sulphur. Oxidizing and reducing properties of sulphu r dioxide as

Investigation of the reactions of

a. halogens with alkalis,

b. halides ions in solution, and

c. solid halides with sulphuric(VI) a

Investigation of the action of heat on

nitrates(V). Brown ring test for nitrate

Investigation of the redox properties o

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11. The d- Block Elements

11.1 General features of the d- block elements

from Sc to Zn

11.2 Characteristic properties of the d- block

elements and their compounds:

(a) Variable oxidation states

(b) Complex formation

exemplified by the reactions with manganate( VII) ion, dichromate( VI) ion,

bromine and magnesium metal. Manufacture of sulphuric( VI) acid by contact

process and itsunderlying physicochemical principles. Sulphuric( VI) acid as an

oxidizing agent and a dehydrating agent.

Test for sulphate( VI) ions. Uses of sulphuric( VI) acid in the manufacture of

fertilizers, detergents, paints, pigments and dyestuffs. Investigation of the redox

properties of sulphur dioxide.

Electronic configurations (linked with Section 2. 4). d- Block elements as metals.

Comparison of ionization enthalpies, electronegativities, melting points,

hardness, densities and reactions with water between d- block and s- block

metals.

Interpretation of the characteristic properties, viz. variable oxidation states,

complex formation, coloured ions, and catalytic properties in terms of electronic

structures, successive ionization enthalpies, atomic and ionic radii.

Studies limited to common oxidation states o f vanadium (+ 2, +3, +4, +5) and

manganese (+ 2, +4, +7). Interconversions of oxidation states of each element.

Studies limited to complexes of Fe( II), Fe( III), Co( II) and Cu( II) with the

following ligands: H 2 O, NH 3 ,Cl and CN .

dioxide.

Test for sulphate(VI) ions using acidi

barium chloride solution.

Investigation of the redox reactions o

or manganese compounds.

Investigation of the relative stability o

copper(II) complexes.

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(c) Coloured ions

(d) Catalytic properties of transition metals

and their compounds

Nomenclature of these complexes. Displacement of ligands and relative stability

of complex ions. (Experimentation involving cyanide ions should notbe

attempted.) (Calculations involving stability constants are notrequired). Stereo-

structures of 4- and 6- coordinated complexes.(Optical isomerism of complexes

is notrequired.)

Studies limited to the hydrated io ns of Fe( II), Fe( III), Co( II) and Cu( II).

Exemplified by the use of Fe in Haber process, Fe 2+or Fe 3+in the reaction

between peroxodisulphate( VI) and iodide ions, and MnO 2 in the decomposition

of hydrogen peroxide (linked with Section5.7).

Investigation of the catalytic action o

ions on the reaction between

peroxodisulphate(VI) and iodide ions

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al chemistry syllabus

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