chemistry - lazsta - home03-08...2008 higher school certificate examination chemistry general...

2008 H I G H E R S C H O O L C E R T I F I C AT E

E X A M I N AT I O N

Chemistry

General Instructions

• Reading time – 5 minutes

• Working time – 3 hours

• Write using black or blue pen

• Draw diagrams using pencil

• Board-approved calculators may be used

• A data sheet and a Periodic Table are provided at the back of this paper

• Write your Centre Number and Student Number at the top of pages 9, 11, 15, 17 and 21

Total marks – 100

Section I Pages 2–23

75 marks

This section has two parts, Part A and Part B

Part A – 15 marks

• Attempt Questions 1–15

• Allow about 30 minutes for this part

Part B – 60 marks


• Allow about 1 hour and 45 minutes for this part

Section II Pages 25–35

25 marks

• Attempt ONE question from Questions 29–33

• Allow about 45 minutes for this section

115

Section I 75 marks

Part A – 15 marks Attempt Questions 1–15 Allow about 30 minutes for this part

Use the multiple-choice answer sheet for Questions 1–15.

1 Which of the following radiations is measured with a Geiger counter?

(A) Beta

(B) Infrared

(C) Microwave

(D) Ultraviolet

2 What are the volumes of one mole of argon, Ar, and one mole of fluorine, F2, at 0°C and 100 kPa?

(A)

(B)

(C)

(D)

Volume (litres)

Ar F2

12.40 24.79

22.71 22.71

22.71 45.42

24.79 24.79

3 Which term describes the relationship between oxygen and ozone?

(A) Allotropes

(B) Conjugates

(C) Isomers

(D) Isotopes

– 2 –

4 What is the main constituent of the atmosphere at ground level?

(A) Water

(B) Oxygen

(C) Nitrogen

(D) Carbon dioxide

5 Why is ethanol used in preference to water as the main ingredient of perfume?

(A) Ethanol is cheaper to produce.

(B) Ethanol has no detectable odour.

(C) Ethanol dissolves esters more readily.

(D) Ethanol has a significantly lower density.

6 What is the specific heat of a compound?

(A) The quantity of heat required to boil 1 g of the compound

(B) The quantity of heat required to melt 1 g of the compound

(C) The quantity of heat required to increase the temperature of the compound by 1°C

(D) The quantity of heat required to increase the temperature of 1 g of the compound by 1° C

7 Which of the following changes will always shift this equilibrium reaction to the right?

2HI(g) � H2(g) + I2(g) ΔH = –52 kJ

(A) Adding a catalyst

(B) Increasing the pressure

(C) Increasing the temperature

(D) Adding more of the reactant

8 According to the Arrhenius theory of acids and bases, an acid is a substance that

(A) tastes sour.

(B) is capable of donating a hydrogen ion.

(C) can accept a pair of electrons to form a co-ordinate covalent bond.

(D) increases the concentration of hydrogen ions in an aqueous solution.

– 3 –

9 Which of the following lower atmosphere pollutant gases is produced directly by the smelting of mineral ores?

(A) Carbo n monoxide

(B) Nitrogen dioxide

(C) Ozone

(D) Sulfur dioxide

10 The molar heat of combustion of ethanol is 1367 kJ mol–1.

What quantity of ethanol must be combusted to raise the temperature of 1.0 kg water from 50°C to boiling point at sea level (assuming no loss of heat to the surroundings)?

(A) 6.5 g

(B) 7.0 g

(C) 209 g

(D) 300 g

11 In which of the following alternatives are the three compounds listed in order of increasing boiling point?

(A) Pentane, butan-1-ol, propanoic acid

(B) Propanoic acid, butan-1-ol, pentane

(C) Propanoic acid, pentane, butan-1-ol

(D) Butan-1-ol, propanoic acid, pentane

– 4 –

12 Samples of water were collected from a river at four different sites: forest, mine, town and estuary.

Ocean

Estuary sampling site

Mine sampling site

Copper mine discharge

Town sampling site

Town sewage treatment plant discharge

Forest catchment Forest sampling site

The results of various analyses of the water samples are shown.

Site 1 Site 2 Site 3 Site 4

pH Total Dissolved Solids (mg/L) Biochemical Oxygen Demand (mg/L) E. coli (CFU/100 mL)

6.8 305 32 18

6.8 85 2 2

7.8 7600

2 2

5.9 290 3 2

Using the data from the table above identify each of the sampling sites.

(A)

(B)

(C)

(D)

Site 1 Site 2 Site 3 Site 4

Town Forest Estuary Mine

Estuary Forest Town Mine

Mine Town Forest Estuary

Town Mine Estuary Forest

– 5 –

13 Some reactions of the metals Q, R and S are given below.

Metal Reaction in air Reaction with water

Reaction with dilute

hydrochloric acid

Q Burns to form metallic oxide

Reacts with steam to form hydrogen

Hydrogen is formed

R Reacts slowly to form metallic oxide

Does not react Does not react

S Reacts to form metallic oxide

Does not react Hydrogen is formed

In a galvanic cell, Q+, R+ and S+ would represent cations of these metals.

Which galvanic cell will produce the greatest voltage?

(A)

Q(s) S(s)

salt bridge

Q+(aq) S+(aq)

V

(B)

S(s) Q(s)

salt bridge

S+(aq) Q+(aq)

V

(C)

Q(s) R(s)

salt bridge

Q+(aq) R+(aq)

V

(D)

S(s) R(s)

salt bridge

S+(aq) R+(aq)

V

– 6 –

14 20 mL of 0.08 mol L–1 HCl is mixed with 30 mL of 0.05 mol L–1 NaOH.

What is the pH of the resultant solution?

(A) 1.1

(B) 2.7

(C) 4.0

(D) 7.0

15 A 2.45 g sample of lawn fertiliser was analysed for its sulfate content. After filtration and drying, 2.18 g of barium sulfate was recovered.

What is the % w/w of sulfate in the lawn fertiliser?

(A) 16.8

(B) 36.6

(C) 46.2

(D) 89.0

– 7 –

BLANK PAGE

– 8 –

© Board of Studies NSW 2008

2008 HIGHER SCHOOL CERTIFICATE EXAMINATION

Chemistry Centre Number

Section I (continued)

Part B – 60 marks Student Number Attempt Questions 16–28 Allow about 1 hour and 45 minutes for this part

Answer the questions in the spaces provided.

Show all relevant working in questions involving calculations.

Marks

2

3

Question 16 (5 marks)

The process of fractional distillation is used to separate crude oil into different fractions. One of the compounds obtained from fractional distillation is C10H22.

This compound undergoes catalytic cracking as follows:

→ + C2H4C10H22 C8H18

(a) Complete the table below to identify the products and the homologous series to which they belong.

C8H18 C2H4

Name of compound

Name of series

(b) Using examples from your first-hand investigation, explain how you distinguished between these two series of compounds. Include a relevant equation in your answer.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

116 – 9 –

Marks

5


Using TWO examples, analyse how the features of catchment areas will determine the water treatment necessary to make the water safe to drink.

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

– 10 –





Student Number

Marks

2

3


(a) Draw Lewis electron dot structures for oxygen and ozone.

(b) Account for the differences in the properties of oxygen and ozone on the basis of their molecular structure and bonding.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

117 – 11 –

Marks

3


A laboratory assesses the amount of zinc in dietary supplement tablets.

A chemist prepared 4 tablet samples for analysis by dissolving the tablets individually in 10% nitric acid. Each tablet solution was made up to a final volume of 100 mL. Five standard solutions of zinc were also prepared.

The absorbances of the standard and sample solutions were determined by atomic absorption spectroscopy at 213.9 nm.

The results are presented in the table.

Standard zinc solutions (mg L–1) Absorbance

0.00 0.000

1.00 0.170

2.00 0.330

3.00 0.503

4.00 0.680

Tablet samples: mean absorbance 0.280

(a) Plot a calibration curve for the standard zinc solutions on the grid.

Question 19 continues on page 13

– 12 –

Marks

2

2

1

Question 19 (continued)

(b) Using the mean absorbance of the tablet samples, calculate the mean amount of zinc per tablet in mg.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

End of Question 19


1.22 g of an unknown gas has a volume of 15.0 L at 100 kPa and 25°C.

(a) Calculate the molar mass of the gas.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

(b) Identify the gas.

...............................................................................................................................

...............................................................................................................................

– 13 –

BLANK PAGE

– 14 –





Student Number

Marks

2

2


The graph shows the concentration of CCl3F known as CFC-11, as measured at the Cape Grim Baseline Air Pollution Station, in north-western Tasmania.

Awaiting copyright

(a) Explain the changes in concentration of CFC-11 as illustrated by the graph.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

(b) Why is it important to monitor the concentration of CFC-11?

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

118 – 15 –

Marks

5


The following extract was taken from the website of a leading car manufacturer.

Awaiting copyright

Critically evaluate the extract with reference to ethanol being a ‘carbon-neutral’ fuel. Support your answer with relevant chemical equations.

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

– 16 –





Student Number

Marks

4


Using Le Chatelier’s principle, justify the choice of temperature and pressure conditions used to optimise the yield in the Haber process.

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

118a – 17 –

Marks

1

2

2


The table shows four fuels and their various properties.

Property Petrol Kerosene Hydrogen Ethanol

Heat of combustion (kJ mol–1) 5460 10 000 285 1370

Boiling point (°C) 126 300 –253 78

Density (g mL–1) 0.69 0.78 n/a 0.78

Average molar mass (g mol–1) 114 210 2 46

(a) Which fuel provides the greatest amount of energy per gram?

...............................................................................................................................

...............................................................................................................................

(b) A car has an 80 L petrol tank. Calculate the energy released by the complete combustion of one full tank of petrol.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

(c) How many litres of hydrogen gas at 25°C and 100 kPa would be needed tosupply the same amount of energy as 80 L of petrol?

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

– 18 –

Ni(NO3)2(aq) (pale green)

v Pt(s)Ni(s)

salt bridge Cl2(g) in

KNO3(aq)

KCl(aq) (colourless)

Marks

1

1

1

2


A galvanic cell under standard conditions is represented below.

(a) On the diagram, clearly label the anode, the cathode and the direction of electron flow.

(b) Write a balanced net ionic equation for the overall cell reaction.

...............................................................................................................................

...............................................................................................................................

(c) Calculate the standard cell potential (E−°).

...............................................................................................................................

...............................................................................................................................

(d) Explain any colour changes observed in this cell as the reaction proceeds.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

– 19 –

BLANK PAGE

– 20 –





Student Number

Marks

4


Explain how a buffer works with reference to a specific example in a natural system.

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

119 – 21 –

Marks

2

2


(a) Classify these salts as forming acidic, basic or neutral solutions.

Salt Classification of solution

Ammonium chloride

Sodium ethanoate

Sodium chloride

Ammonium nitrate

(b) From the table, choose a salt that forms an acidic or basic solution, and justify its classification. Include an equation to illustrate your answer.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

– 22 –

Marks

2

1

3


A standard solution was prepared by dissolving 1.314 g of sodium carbonate in water. The solution was made up to a final volume of 250.0 mL.

(a) Calculate the concentration of the sodium carbonate solution.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

This solution was used to determine the concentration of a solution of hydrochloric acid. Four 25.00 mL samples of the acid were titrated with the sodium carbonate solution. The average titration volume required to reach the end point was 23.45 mL.

(b) Write a balanced equation for the titration reaction.

...............................................................................................................................

(c) Calculate the concentration of the hydrochloric acid solution.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

– 23 –

BLANK PAGE

– 24 –



Chemistry

Section II

25 marks Attempt ONE question from Questions 29–33 Allow about 45 minutes for this section

Answer the question in a writing booklet. Extra writing booklets are available.


Pages

Question 29 Industrial Chemistry ............................................................. 26–27

Question 30 Shipwrecks, Corrosion and Conservation ............................ 28–29

Question 31 The Biochemistry of Movement .......................................... 30–31

Question 32 The Chemistry of Art ........................................................... 32–33

Question 33 Forensic Chemistry .............................................................. 34–35

120 – 25 –

Marks

2

2

2

Question 29 — Industrial Chemistry (25 marks)

(a) The following diagram illustrates the process used to extract sulfur from underground deposits.

Awaiting copyright

(i) Copy and complete this table in your writing booklet to identify which fluid is pumped through each pipe.

Pipe Fluid

Pipe 1

Pipe 2

Pipe 3

Do NOT write your answers here.

(ii) Explain why this process can be used to extract sulfur.

(iii) What possible environmental issues are associated with this process?


– 26 –

Marks

3

2

1

3

3

7


(b) A first-hand investigation was performed to observe the electrolysis of sodium chloride.

(i) Describe an appropriate procedure.

(ii) Identify the reactions that occur at the anode and at the cathode and give equations for these reactions.

(iii) What condition would need to be changed to produce sodium metal as a product?

(c) Consider the following mixture of gases in a closed 5.0 L vessel at 730°C.

Gas Quantity (mol)

CH4 2.00

H2O 1.25

CO 0.75

H2 0.75

The following reaction occurs:

CH (g) + H O(g) � CO(g) + 3H (g) ΔH 4 2 2 = +206 kJ

The equilibrium constant, K, is 0.26 at 730°C.

(i) Determine whether the system is at equilibrium.

(ii) Explain how conditions in this reaction could be adjusted to increase the quantity of products.

(d) Synthetic detergents have been developed over the past 60 years.

Compare anionic, cationic and non-ionic synthetic detergents in terms of their use and chemical composition and the impact that these detergents have had on the environment.

End of Question 29

– 27 –

Marks

3

3

3

2

1

Question 30 — Shipwrecks, Corrosion and Conservation (25 marks)

(a) Underground gas pipelines are often made of steel. To prevent the pipe from rusting it is connected at regular intervals to metal rods.

steel pipe

conducting wire

metal rod

ground

moist soil

(i) Identify a suitable metal for the rod and explain how this prevents corrosion of the pipe. Support your answer with relevant chemical equations.

(ii) Suggest TWO other methods that could be used to protect the pipe from corrosion and explain how each of these methods is effective.

(b) A first-hand investigation was performed to compare the rate of corrosion of iron and a named steel.


(ii) Explain the results obtained using relevant equations.

(iii) How can steel composition be modified to increase corrosion resistance?


– 28 –

Marks

2

2

2

7


(c) A 1.0 mol L–1 solution of silver nitrate was electrolysed using platinum electrodes.

Silver was produced at one electrode and a gas was produced at the other.

(i) Draw a labelled diagram to represent this cell.

(ii) Identify the reactions that occur at the anode and the cathode and give equations for these reactions.

(iii) Identify FOUR factors that affect the rate of deposition of silver.

(d) Several maritime archaeological projects exist around Australia. Compare the conservation and restoration techniques used in TWO of these projects with reference to the chemistry applied.

End of Question 30

– 29 –

X Y

+ P

Cytochrome chain enzymes catalyse

reaction of NADH + H+

and FADH2 with X to produce Y. Energy

released by this reaction converts ADP + P to ATP.

ADP ATP

Marks

1

2

3

3

2

1

Question 31 — The Biochemistry of Movement (25 marks)

(a) The following flowchart outlines a specific section of an important biochemical process.

(i) Identify X and Y in your writing booklet.

(ii) Identify this biochemical process and the specific section outlined by the flowchart.

(iii) With reference to X and Y explain the role of the co-factors NADH and FADH2. Include equations in your answer.

(b) A first-hand investigation was performed to observe the effects of changes in temperature on the reaction of a named enzyme.


(ii) Sketch an appropriate graph to represent the results.

(iii) Identify the group of biochemical compounds to which this enzyme belongs.


– 30 –

Marks

1

2

3

7


(c) The nutrition information below appeared on the packaging of a food item.

Awaiting copyright

(i) Identify THREE major nutrient groups listed in the panel that are required for human cellular metabolic processes.

(ii) Quantitatively compare the total energy of the contents of this package with the suggested average daily adult intake.

(iii) Explain how the contents of this package could meet the metabolic requirements of human Type 1 skeletal muscle fibres.

(d) With reference to the body’s metabolic processes, analyse how modern athletes might modify their diet over time to cope with a change in focus from less strenuous exercise to sprinting.

End of Question 31

– 31 –

Ene

rgy

[CoCl4]2−

blue solution

[Co(H2O)6]2+

red solution

Marks

2

3

1

3

2

1

Question 32 — The Chemistry of Art (25 marks)

(a) The diagram below shows the ground state electron configuration of two complexes of cobalt in aqueous solution.

(i) Identify the block in the periodic table to which cobalt belongs and write the electron configuration of cobalt metal in its ground state.

(ii) Explain the difference in the colour of the two complexes.

(iii) Why are solutions of zinc complexes colourless?

(b) A first-hand investigation was performed to demonstrate the oxidising strength of potassium permanganate.


(ii) Explain the results obtained with the use of half equations.

(iii) A solution of potassium permanganate was added to solutions of the following three compounds: potassium iodide, potassium bromide and potassium fluoride.

Identify which of these solutions would react with the potassium permanganate.


– 32 –

Marks

3

2

1

7


(c) An acidified solution of VO +2 (aq) is poured into a flask containing zinc metal.

When the flask is swirled the following sequence of colour changes is observed.

yellow green blue violet

VO +(aq) VO2+(aq2 ) V3+(aq) V2+(aq)

(i) Sketch the expected absorption spectrum for the violet V2+(aq) solution and justify the shape of the curve you have drawn.

(ii) Use the following unbalanced half equations to give the overall equation for the colour change from yellow to violet.

Zn(s) → Zn2+(aq) + e –

VO +( ) + H+( ) + e – → V2+aq aq (aq) + H O(l2 2 )

(iii) Identify the class of reaction to which the reactions in part (ii) belong.

(d) A painting is discovered in a disused storeroom of a local museum. The style suggests the painting is approximately 500 years old.

Describe some methods a chemist would use to identify pigments in the painting and to check the estimated age of the painting.

End of Question 32

– 33 –

Marks

2

4

Question 33 — Forensic Chemistry (25 marks)

(a) At a crime scene secured by police, it appears a motor vehicle has been driven into a plate glass window. Display cases inside the window are empty and the vehicle is gone. The forensic examiner made the following annotated sketch.

TELEVISION ELECTRONICS SHOP 112

Fingerprintson shelves

Threads of cloth

Glass shards

Glass fragmentsheadlight glass

Blood dropson glass

Muddy tyretracks

s

Glass fragm headlight g

g

dy tyre acksy y

Oily patch h

G h

Glass shards from window,paint flakes on glass shards

(i) Identify FOUR pieces of evidence that could be collected to help solve the crime.

(ii) Identify TWO instrumental techniques and explain how each could be used to analyse the evidence collected from this crime scene.


– 34 –

Marks

3

2

1

1

2

3

7


(b) A first-hand investigation was performed to identify reducing and non-reducing sugars.


(ii) Account for the results obtained in terms of the chemical differences between reducing and non-reducing sugars.

(iii) Suggest an instrumental method for identifying different sugars.

(c) An athlete provided a urine sample to be tested for steroids. The sample and the steroid standards were treated and then analysed by gas chromatography with mass spectrometric detection.

Below are chromatograms of a standard mixture containing four different steroids, and the sample from the athlete.

Standard steroid mixture Sample from athlete

Inte

nsity

Stan

ozol

ol3. 4.

Pre

dnis

olon

e

1. N

andr

olon

e

2. N

oran

dros

tero

ne

Inte

nsity

1 2 3 4 5 6 7 Time (min)

8 9 1 2 3 4 5 Time (min)

6 7 8 9

(i) Identify which steroid, if any, the athlete has taken.

(ii) What properties of compounds would lead a forensic chemist to use high pressure liquid chromatography over gas chromatography?

(iii) Describe the principle of operation of the mass spectrometer. Include a diagram in your answer.

(d) With reference to a named example, explain the theory behind emission spectra and how such information could be useful in determining the origins of a mixture.

End of paper – 35 –

BLANK PAGE

– 36 –



Chemistry

DATA SHEET

1023 mol–1 Avogadro constant, NA .................................................................. 6.022 ×

Volume of 1 mole ideal gas: at 100 kPa and at 0°C (273.15 K) ...................... 22.71 L at 25°C (298.15 K) .................... 24.79 L

10–14 Ionisation constant for water at 25°C (298.15 K), K ................. 1.0 × w

103 J kg–1 K–1 Specific heat capacity of water ..................................................... 4.18 ×

Some useful formulae pH = –log10[H+ ] ΔH = –m C ΔT

Some standard potentials –K+ + e K(s) –2.94 V

Ba2+ + 2e– Ba(s) –2.91 V

Ca2+ + 2e– Ca(s) –2.87 V

–Na+ + e Na(s) –2.71 V

Mg2+ + 2e– Mg(s) –2.36 V

Al3+ + 3e– Al(s) –1.68 V

Mn2+ + 2e– Mn(s) –1.18 V

–H2O + e – –1 H2(g) + OH2 –0.83 V

Zn2+ + 2e– Zn(s) –0.76 V

Fe2+ + 2e– Fe(s) –0.44 V

Ni2+ + 2e– Ni(s) –0.24 V

Sn2+ + 2e– Sn(s) –0.14 V

Pb2+ + 2e– Pb(s) –0.13 V

– H+ + e 1–H2(g) 2 0.00 V

2– +SO4 4H+ + 2e– SO (aq) + 2H O 2 2 0.16 V

Cu2+ + 2e– Cu(s) 0.34 V

1–O2(g) + H2O + 2e– 2

–2OH 0.40 V

–Cu+ + e Cu(s) 0.52 V

– –1 I2(s) + e2 I– 0.54 V

1 – –I2(aq) + e 2 I– 0.62 V

–Fe3+ + e Fe2+ 0.77 V

–Ag+ + e Ag(s) 0.80 V

– –1 Br2(l) + e2 Br– 1.08 V

1 – –Br2(aq) + e 2 Br– 1.10 V

1–O2(g) + 2H+ + 2e– 2 H2O 1.23 V

1 – –Cl2(g) + e 2 Cl– 1.36 V

1 2– +–Cr2O7 7H+ + 3e– 2 Cr3+ + –7 H2O 2 1.36 V

1 – –Cl2(aq) + e 2 Cl– 1.40 V

–MnO4 + 8H+ + 5e– Mn2+ + 4H2O 1.51 V

1 – –F2(g) + e 2 – F 2.89 V

Aylward and Findlay, SI Chemical Data (5th Edition) is the principal source of data for this examination paper. Some data may have been modified for examination purposes.

– 37 –

120a

– 38 –

PE

RIO

DIC

TA

BL

E O

F T

HE

EL

EM

EN

TS

12

HH

e1.

008

4.00

3H

ydro

gen

KE

Y

Hel

ium

Ato

mic

Num

ber

34

795

67

89

10Sy

mbo

l of

elem

ent

Li

Be

Au

BC

NO

FN

e6.

941

9.01

2A

tom

ic W

eigh

t 19

7.0

10.8

112

.01

14.0

116

.00

19.0

020

.18

Lith

ium

B

eryl

lium

G

old

Nam

e of

ele

men

t B

oron

Car

bon

Nitr

ogen

Oxy

gen

Fluo

rine

Neo

n

1112

1314

1516

1718

Na

Mg

Al

SiP

SC

lA

r22

.99

24.3

126

.98

28.0

930

.97

32.0

735

.45

39.9

5So

dium

M

agne

sium

A

lum

iniu

mSi

licon

Ph

osph

orus

Sulf

ur

Chl

orin

eA

rgon

1920

2122

2324

2526

2728

2930

3132

3334

3536

KC

aSc

Ti

VC

rM

nFe

Co

Ni

Cu

Zn

Ga

Ge

As

SeB

rK

r39

.10

40.0

844

.96

47.8

750

.94

52.0

054

.94

55.8

558

.93

58.6

963

.55

65.4

169

.72

72.6

474

.92

78.9

679

.90

83.8

0Po

tass

ium

C

alci

um

Scan

dium

T

itani

um

Van

adiu

m

Chr

omiu

m

Man

gane

se

Iron

C

obal

t N

icke

l C

oppe

r Z

inc

Gal

lium

Ger

man

ium

A

rsen

icSe

leni

um

Bro

min

eK

rypt

on

3738

3940

4142

4344

4546

4748

4950

5152

5354

Rb

SrY

Zr

Nb

Mo

Tc

Ru

Rh

PdA

gC

dIn

SnSb

TeI

Xe

85.4

787

.62

88.9

191

.22

92.9

195

.94

[97.

91]

101.

110

2.9

106.

410

7.9

112.

411

4.8

118.

712

1.8

127.

612

6.9

131.

3R

ubid

ium

St

ront

ium

Y

ttriu

m

Zir

coni

um

Nio

bium

M

olyb

denu

m

Tech

netiu

m

Rut

heni

um

Rho

dium

Pa

lladi

um

Silv

er

Cad

miu

m

Indi

umT

in

Ant

imon

yTe

lluri

um

Iodi

neX

enon

5556

57–7

172

7374

7576

7778

7980

8182

8384

8586

Cs

Ba

Hf

TaW

Re

Os

IrPt

Au

Hg

Tl

PbB

iPo

At

Rn

132.

913

7.3

178.

518

0.9

183.

818

6.2

190.

219

2.2

195.

119

7.0

200.

620

4.4

207.

220

9.0

[209

.0]

[210

.0]

[222

.0]

Cae

sium

B

ariu

m

Lan

than

oids

H

afni

um

Tant

alum

T

ungs

ten

Rhe

nium

O

smiu

m

Irid

ium

Pl

atin

um

Gol

d M

ercu

ry

Tha

llium

L

ead

Bis

mut

h Po

loni

um

Ast

atin

e R

adon

8788

89–1

0310

410

510

610

710

810

911

011

1Fr

Ra

Rf

Db

SgB

hH

sM

tD

sR

g[2

23]

[226

][2

61]

[262

][2

66]

[264

][2

77]

[268

][2

71]

[272

]Fr

anci

um

Rad

ium

A

ctin

oids

R

uthe

rfor

dium

D

ubni

um

Seab

orgi

um

Boh

rium

H

assi

um

Mei

tner

ium

D

arm

stad

tium

R

oent

geni

um

Lan

than

oids

5758

5960

6162

6364

6566

6768

6970

71L

aC

ePr

Nd

PmSm

Eu

Gd

Tb

Dy

Ho

Er

Tm

Yb

Lu

138.

914

0.1

140.

914

4.2

[145

]15

0.4

152.

015

7.3

158.

916

2.5

164.

916

7.3

168.

917

3.0

175.

0L

anth

anum

Cer

ium

Pr

aseo

dym

ium

N

eody

miu

m

Prom

ethi

um

Sam

ariu

m

Eur

opiu

m

Gad

olin

ium

Te

rbiu

m

Dys

pros

ium

H

olm

ium

E

rbiu

m

Thu

lium

Y

tterb

ium

L

utet

ium

Act

inoi

ds

8990

9192

9394

9596

9798

9910

010

110

210

3A

cT

hPa

UN

pPu

Am

Cm

Bk

Cf

Es

FmM

dN

oL

r[2

27]

232.

023

1.0

238.

0[2

37]

[244

][2

43]

[247

][2

47]

[251

][2

52]

[257

][2

58]

[259

][2

62]

Act

iniu

m

Tho

rium

Pr

otac

tiniu

m

Ura

nium

N

eptu

nium

Pl

uton

ium

A

mer

iciu

m

Cur

ium

B

erke

lium

C

alif

orni

um

Ein

stei

nium

Fe

rmiu

m

Men

dele

vium

N

obel

ium

L

awre

nciu

m

For

elem

ents

that

hav

e no

sta

ble

or lo

ng-l

ived

nuc

lides

, the

mas

s nu

mbe

r of

the

nucl

ide

with

the

long

est c

onfi

rmed

hal

f-lif

e is

list

ed b

etw

een

squa

re b

rack

ets.

T

he I

nter

natio

nal U

nion

of

Pure

and

App

lied

Che

mis

try

Peri

odic

Tab

le o

f th

e E

lem

ents

(O

ctob

er 2

005

vers

ion)

is th

e pr

inci

pal s

ourc

e of

dat

a. S

ome

data

may

hav

e be

en m

odif

ied.

2007 H I G H E R S C H O O L C E R T I F I C AT E


Chemistry








• Write your Centre Number and Student Number at the top of pages 9, 13, 15, 17 and 21

Total marks – 100


75 marks


Part A – 15 marks



Part B – 60 marks




25 marks



115

Section I 75 marks


Use the multiple-choice answer sheet for Questions 1–15.

1 Which of the following is a renewable resource?

(A) Ethanol

(B) Uranium

(C) Petroleum

(D) Aluminium

2 What type of reaction describes the polymerisation of glucose into cellulose?

(A) Addition

(B) Hydrolysis

(C) Substitution

(D) Condensation

3 In a galvanic cell, what is the pathway of electron flow?

(A)

(B)

(C)

(D)

Direction Medium

anode to cathode salt bridge

anode to cathode external wire

cathode to anode salt bridge

cathode to anode external wire

– 2 –

4 What is the IUPAC name for the following compound?

HH H

C H H H H H

H C C CC C C C H

H H H OH H H

5 The diagram represents a cell in which two metals have been placed in a solution containing their respective metallic ions. The metals are connected to a voltmeter.

(A) Hexan-3-ol

(B) Hexan-4-ol

(C) Heptan-3-ol

(D) Heptan-5-ol

V

Which of the following combinations of metals would produce the highest reading on the voltmeter?

(A) Tin and zinc

(B) Copper and zinc

(C) Copper and silver

(D) Magnesium and lead

– 3 –

6 Which aqueous solution turns phenolphthalein pink?

(A) HCl

(B) NaCl

(C) NaOH

(D) CH3OH

7 Which graph represents the enthalpy change for an acid-base neutralisation reaction?

Ent

halp

y

Reaction progress

Ent

halp

y

(A)

(C)

Ent

halp

y

Reaction progress

Ent

halp

y

(B)

(D)

Reaction progress Reaction progress

8 Acid X and acid Y are both monoprotic weak acids of equal concentration. Acid X is a stronger acid than acid Y.

Which statement about acid X and acid Y is correct?

(A) Acid Y is completely ionised in solution.

(B) The solution of acid X is less ionised than the solution of acid Y.

(C) The solution of acid X has a lower pH than the solution of acid Y.

(D) 1 mole of acid Y requires a greater volume of 1.0 mol L–1 NaOH for neutralisation than 1 mole of acid X.

9 Which of the following aqueous solutions has a pH greater than 7?

(A) Sodium citrate

(B) Sodium chloride

(C) Ammonium nitrate

(D) Ammonium chloride

– 4 –

10 A 0.1 mol L–1 HCl solution has a pH of 1.0 .

What volume of water must be added to 90 mL of this solution to obtain a final pH of 2.0?

(A) 10 mL

(B) 180 mL

(C) 810 mL

(D) 900 mL

11 What is the consequence of having large concentrations of Mg2+ and Ca2+ ions in waterways?

(A) Turbidity

(B) Hardness

(C) Eutrophication

(D) Heavy metal contamination

12 Which of the following is always produced during combustion of fossil fuels?

(A) Water

(B) Carbon (soot)

(C) Sulfur dioxide

(D) Carbon dioxide

13 Consider the following reaction at equilibrium.

N2(g) + 3H2(g) 2NH3(g) ΔH = –92 kJ mol–1

What would be the effect of a decrease in pressure on this system?

(A) Heat will be absorbed.

(B) The equilibrium will not be disturbed.

(C) The concentration of NH3 will increase.

(D) The reverse rate of reaction will decrease.

– 5 –

14 Which statement about Atomic Absorption Spectroscopy (AAS) is correct?

(A) AAS is an effective qualitative technique but it cannot be used for quantitative analysis.

(B) AAS measures the wavelengths of light emitted when electrons fall back to their ground state.

(C) In AAS, white light is shone through a vaporised sample in order to observe which wavelengths are absorbed.

(D) The wavelength of light used in AAS matches one of the spectral lines produced when the sample is analysed by a flame test.

15 The following equations show the overall effect of the presence of chlorine free radicals (•Cl) on ozone in the stratosphere.

•Cl + O3 → •ClO + O2

•ClO + •O → •Cl + O2

Which term best describes the role of the chlorine free radical in this process?

(A) Anion

(B) Catalyst

(C) Initiator

(D) Oxidant

– 6 –

BLANK PAGE

– 7 –

BLANK PAGE

– 8 –








Marks

1

4


The diagram represents a section of the layered structure of Earth’s atmosphere.

Earth

X 15 km

Y 35 km

(a) Identify the layers of atmosphere labelled X and Y.

X .............................................................................

Y .............................................................................

(b) Ozone is a gas found in layers X and Y.

Explain the effect of ozone in each of these layers.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

116 – 9 –

Marks Question 17 (4 marks)

Each of the four bottles contains one of the following solutions:

• barium nitrate

• hydrochloric acid

• lead nitrate

• sodium carbonate.

solution 1 solution 2 solution 3 solution 4

A student mixed pairs of these solutions together and obtained the following results.

Reactants Observation

solution 1 and solution 2 bubbles

solution 2 and solution 3 white precipitate

solution 2 and solution 4 no reaction



(a) Write a correctly balanced equation to represent the reaction between solution 1 and solution 2.

...............................................................................................................................


– 10 –

1

Marks

2

1

3


(b) Use the information to identify the four solutions.

Solution Identity

1

2

3

4

(c) Why would it be inappropriate to use flame tests to identify these solutions?

...............................................................................................................................

...............................................................................................................................


Describe the role of a chemist employed in an industry or enterprise, and a chemical principle used by the chemist. (Choose an occupation other than teaching.)

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

– 11 –

BLANK PAGE

– 12 –




Section I – Part B (continued)

Student Number

Marks

7


There are many benefits and problems associated with the use of radioisotopes in industry and medicine.

Evaluate the impact on society of the use of radioisotopes in both industry and medicine. In your answer, give examples of specific radioisotopes, making reference to their chemical properties.

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

117 – 13 –


The diagram represents a typical car battery.

As the battery discharges, the following half reactions occur:

Pb(s) + SO2–4 (aq) → PbSO (s) + 2e–

4

PbO2(s) + SO2–4 (aq) + 4H+(aq) + 2e– → PbSO4(s) + 2H2O(l)

(a) Identify the anode, then write the equation that represents the overall chemicalreaction.

...............................................................................................................................

...............................................................................................................................

(b) Explain one benefit of car batteries lasting several years.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

H2SO4solution

PbO2 Pb

Chemistry 2, HSC Course, by Thickett, Jacaranda Science / Wiley, 1st Edition, © 2006; Reprinted with permission of John Wiley & Sons Australia

– 14 –

Marks

2

2



Chemistry


Centre Number

Student Number

Marks

1

1

3


Red cabbage indicator chart

Colour red violet purple blue green yellow

pH 1 2 3 4 5 6 7 8 9 10 11 12 13 14

(a) State what colour the red cabbage indicator would be in a 0.005 mol L–1 solution of H2SO4. Show your working.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

(b) Using the red cabbage indicator, what colour would the solution be if 10 mL of 0.005 mol L–1 H2SO4 was diluted to 100 mL?

...............................................................................................................................

...............................................................................................................................

(c) What volume of 0.005 mol L–1 KOH is required to neutralise 15 mL of the diluted solution of H2SO4?

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

118 – 15 –


The following article was sourced from the internet.

In 2004, Australia’s Minister for the Environment announced that the allowableamounts of sulfur in unleaded petrol and diesel would be reduced over the next 5years.

Currently sulfur in diesel is 500 parts per million (ppm) but it will be cut to 50ppm on 1 January 2006 and capped at 10 ppm from January 2009.

(a) Calculate the volume of sulfur dioxide produced when a full tank(capacity 60 kg) of diesel is consumed at 25°C and 100 kPa in November 2007.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

(b) Evaluate the effect of the sulfur reduction policy on the environment.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

– 16 –

Marks

3

4





Student Number

Marks

3


When hexanoic acid and ethanol are mixed together under certain conditions, esterification occurs.

Describe the conditions necessary for this reaction and give the structural formulae and names of the products.

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

118a – 17 –

Marks

3


The heats of combustion (–ΔH ) of three alkanols were determined.c

The results are shown in the table.

Alkanol Heat of combustion (kJ mol–1)

methanol

ethanol

butan-1-ol

480

920

1800

(a) Plot a graph of the heat of combustion versus the molecular weight for the three alkanols.

Molecular weight


– 18 –

Marks

1

1


(b) (i) Use the graph to estimate the heat of combustion of propan-1-ol.

...................................................................................................................

...................................................................................................................

(ii) The theoretical value for the heat of combustion of propan-1-ol is more than 2000 kJ mol–1.

Suggest a chemical reason, other than heat loss, for the difference between this value and the estimated value from part (b) (i).

...................................................................................................................

...................................................................................................................

End of Question 24

– 19 –

Marks

5


Sodium hydrogen carbonate, NaHCO3, is commonly used to neutralise chemical spillsthat are a potential hazard to the environment.

Assess the effectiveness of NaHCO3 in this role, with reference to its chemical properties.

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

– 20 –





Student Number

Marks

4


Explain how the structure and properties of polyethylene and polystyrene relate to theway each is used.

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

119 – 21 –


The diagrams represent equipment used in an investigation to determine thechloride ion concentration in a water sample.

AgNO3solution Precipitate

Vacuumpump

Filtrate

Sinteredglass filter

Watersample

Figure 1 Figure 2

Reproduced by Permission of Macmillan Education Australia

(a) Describe how you could, using the equipment in the diagram, determine thechloride ion concentration in a water sample. Include a balanced equation.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................


– 22 –

Marks

3

Marks

3

2


(b) If the volume of the water sample being tested is 50.0 mL and the mass of the dried precipitate obtained is 3.65 g, calculate the chloride ion concentration in the water sample in ppm.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

(c) Why is it important to determine the chloride ion concentration in water?

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

End of Question 27

– 23 –

BLANK PAGE

– 24 –



Chemistry

Section II




Pages






120 – 25 –

Marks Question 28 — Industrial Chemistry (25 marks)

(a) The diagram is a flowchart of the reactions involved in an important industrial process.

NaCl(aq)

brine purification

ammonia absorber

lime dissolver

heat

filter tower CaO(s)

NaHCO3

NH4Cl

NH3(g)

CaCl2(aq)

water

water

heatfurnace CaCO3(s)

Ca(OH)2(aq) NH3(aq)NaCl(aq)

NH4Cl

NaHCO3

CO2(g)

Na2CO3(s)

(i)

(ii)

Identify this industrial process and write a balanced equation to represent the overall chemical reaction that occurs.

The products of the reaction formed in the tower are sodium hydrogen carbonate and ammonium chloride.

Describe how these two substances are separated.

2

2


– 26 –

Marks

6

1

2

2

4

2

1

3


(b) Over the past century the production of sodium hydroxide has evolved from the mercury process, to the diaphragm process, to the membrane process.

Analyse the factors that contributed to each of the changes in the production process.

(c) Hydrogen sulfide can be removed from natural gas via the following process.

2H2S(g) + SO2(g) 3S(s) + 2H2O(g) ΔH = –145 kJ mol–1

(i) Write the equilibrium constant expression for this reaction.

(ii) Calculate the equilibrium constant, when 1.00 mol of H2S and 1.00 mol of SO2 react in a 1.00 L vessel at 373 K to give 0.50 mol of water vapour under equilibrium conditions.

(iii) Identify FOUR factors that would maximise the removal of H2S(g) in this reaction.

(d) Describe the impact that saponification products have had on society and the environment.

(e) You performed a first-hand investigation to model an equilibrium reaction.

(i) Outline the procedure used and the results you obtained.

(ii) Identify a risk associated with this procedure.

(iii) Describe how this procedure models equilibrium and state a limitation of the model.

End of Question 28

– 27 –

Marks

2

2

6


(a) The diagram shows an electrolytic cell.

Graphite rods

QP A coating builds up on electrode P

Bubbles of gas form on electrode Q

Dilute copper sulfate solution

(i) Explain why graphite rods are used in an electrolytic cell.

(ii) Describe, with the use of half equations, the processes that occur at the anode and cathode.

(b) Corrosion is a major problem for vessels that have to operate in a variety of aquatic environments.

Analyse how the factors in aquatic environments have impacted on the choice of metals used in the construction of vessels over time.


– 28 –

Marks

1

2

2

4

2

1

3


(c) The diagram represents three separate petri dishes each containing a mixture of agar, sodium chloride solution, phenolphthalein and an indicator which turns blue in the presence of Fe2+. Nails are added to each dish.

Dish A Nail

blue

blue pink

Dish B Nail with Cu wire

blue

blue

pink

Cu

pink

pink

Mg

Dish C Nail with Mg ribbon

(i) Why does the mixture contain sodium chloride solution?

(ii) Write two half equations to explain the presence of the blue and pink colours in dish B.

(iii) In which dish would the nail be protected from corrosion? Explain your answer.

(d) The work of early scientists has increased our understanding of electron transfer reactions. Describe the impact of this work on society.

(e) You performed a first-hand investigation to compare and describe the rate of corrosion of metals in different acidic and neutral solutions.



(iii) Use your results to explain why shipwrecks at great depth experience accelerated corrosion.

End of Question 29

– 29 –

Marks

2

2

6


The flowchart outlines an important biological process.

(a) Proteins

Amino acids Glucose

Glycolysis

CO2

Fatty acids and glycerol

LipidsCarbohydrates

Acetyl-CoA

W

(i) Identify substance W and the site where it undergoes oxidation to form acetyl-CoA.

(ii) Identify the form in which energy is captured, and account for the overall number of these molecules produced per glucose molecule duringglycolysis.

(b) In the study of chemistry, scientists use models to test and relate ideas.

Analyse how the use of models or diagrams has contributed to ourunderstanding of the structure and chemical features of carbohydrates, fats and proteins.


– 30 –

Marks

1

2

2

4

2

1

3


(c) (i) State an IUPAC name for the substance with the common name, lactic acid, C3H6O3.

(ii) Using structural formulae, write the balanced equation for the formation of lactic acid in anaerobic respiration.

(iii) The production of lactic acid results in a change in cellular pH.

Explain the impact this would have on muscles.

(d) Describe how knowledge of aerobic respiration has increased our understanding of muscle activity during gentle exercise.

(e) You performed a first-hand investigation to observe the effect of changes in pH on the reaction of a named enzyme.



(iii) Enzymes will only function at a specific pH. Explain this in terms of their structure.

End of Question 30

– 31 –

Marks

3

1

6

1

2

2

4


(a) The electron spin orbital diagram represents the 3d and 4s electrons for an element in the first transition series.

3d 4s

(i) Identify this element and explain the arrangement of electrons in these sub-shells in terms of the Pauli exclusion principle and Hund’s rule.

(ii) This element can form an ion with an oxidation state of +3. In your writing booklet, draw an electron spin orbital diagram to represent this ion.

(b) In the study of chemistry, scientists use models to test and relate ideas.

Analyse the contribution of using Lewis models in the development of our understanding of the structure of complex ions formed by transition metals. Use specific examples in your answer.

(c) Transition elements can have variable oxidation states.

(i) Determine the oxidation state of manganese in MnO – 4 and MnO2.

(ii) Explain which of these two species would be the stronger oxidising agent.

(iii) Write a half-equation to represent the oxidation of the Cr3+(aq) ion to form the acidified dichromate ion Cr O 2–(aq2 7 ) and give an example of an oxidising agent that would cause this to happen.

(d) Describe how our understanding of the chemistry of specific pigments used by an ancient culture has influenced our choice of pigments used today.


– 32 –

Marks

2

1

3


(e) You have performed a first-hand investigation to observe the flame colour of a number of different cations.

(i) Outline the procedure you used to identify the Sr2+ ion.


(iii) Explain how the flame colour of the Sr2+ ion relates to electron excitation and emission spectra.

End of Question 31

– 33 –

Marks

1

3

6


(a) The structure represents fructose.

H

HO C H

H O

C C H OH H

OH C C C OH

OH H H

(i) What is the molecular formula for this compound?

(ii) Sucrose is a disaccharide formed from fructose and another monosaccharide.

Identify the other monosaccharide and explain why these two monosaccharides are reducing sugars whereas sucrose is not.

(b) Evaluate the implications of the use of DNA as an identification molecule for society.


– 34 –

Marks

1

2

2

4

2

1

3


(c) (i) What is the general structural formula for an amino acid?

(ii) The structure represents a specific dipeptide.

H

H H O H C H O

H C C CC N C C

OHH N H H H

H

Using structural formulae, write a balanced equation to show the cleaving of the peptide bond.

(iii) Outline how proteins can be broken into different lengths in the chain.

(d) Describe how the results of some forensic investigations are improved by the use of mass spectrometry.

(e) You performed first-hand investigations to separate mixtures by both chromatography and electrophoresis.

(i) Describe the chromatography procedure you used.


(iii) Explain how the different properties of mixtures enable them to be separated by chromatography and electrophoresis.

End of paper

– 35 –

BLANK PAGE

– 36 –



Chemistry

DATA SHEET

Avogadro constant, NA .................................................................. 6.022 × 1023 mol–1

Volume of 1 mole ideal gas: at 100 kPa and at 0°C (273.15 K) ...................... 22.71 L at 25°C (298.15 K) .................... 24.79 L

Ionisation constant for water at 25°C (298.15 K), K ................. 1.0 × 10–14 w

Specific heat capacity of water ..................................................... 4.18 × 103 J kg–1 K–1

Some useful formulae pH = –log10[H+ ] ΔH = –m C Δ T

Some standard potentials

–K+ + e K(s) –2.94 V

Ba2+ + 2e– Ba(s) –2.91 V

Ca2+ + 2e– Ca(s) –2.87 V

–Na+ + e Na(s) –2.71 V

Mg2+ + 2e– Mg(s) –2.36 V

Al3+ + 3e– Al(s) –1.68 V

Mn2+ + 2e– Mn(s) –1.18 V

–H2O + e –1 H2(g) + OH– –0.83 V 2

Zn2+ + 2e– Zn(s) –0.76 V

Fe2+ + 2e– Fe(s) –0.44 V

Ni2+ + 2e– Ni(s) –0.24 V

Sn2+ + 2e– Sn(s) –0.14 V

Pb2+ + 2e– Pb(s) –0.13 V

– 1H+ + e –2 H2(g) 0.00 V

SO42– + 4H+ + 2e– SO2(aq) + 2H2O 0.16 V

Cu2+ + 2e– Cu(s) 0.34 V

1 – –O2(g) + H2O + 2e– 2OH 0.40 V2 –Cu+ + e Cu(s) 0.52 V

1 – I– –I2(s) + e 0.54 V2 – I– –1 I2(aq) + e 0.62 V2

–Fe3+ + e Fe2+ 0.77 V

–Ag+ + e Ag(s) 0.80 V

–1 Br2(l) + e– Br– 1.08 V2

–1 Br2(aq) + e– Br– 1.10 V2

1–O2(g) + 2H+ + 2e– H2O 1.23 V2

1 – –2 Cl2(g) + e Cl– 1.36 V

1 2– + 7H+ + 3e– –2 Cr2O7 Cr3+ + –7 H2O 1.36 V2

1 – –Cl2(aq) + e Cl– 1.40 V2 –MnO4 + 8H+ + 5e– Mn2+ + 4H2O 1.51 V

1 – – –2 F2(g) + e F 2.89 V

Aylward and Findlay, SI Chemical Data (5th Edition) is the principal source of data for this examination paper. Some data may have been modified for examination purposes. 120a

– 37 –

– 38 –

9 F19

.00

Fluo

rine

17 Cl

35.4

5C

hlor

ine

35 Br

79.9

0B

rom

ine

53 I12

6.9

Iodi

ne

85 At

[210

.0]

Ast

atin

e

7 N14

.01

Nitr

ogen

15 P30

.97

Phos

phor

us

33 As

74.9

2A

rsen

ic

51 Sb12

1.8

Ant

imon

y

83 Bi

209.

0B

ism

uth

5 B10

.81

Bor

on

13 Al

26.9

8A

lum

iniu

m

31 Ga

69.7

2G

alliu

m

49 In11

4.8

Indi

um

81 Tl

204.

4T

halli

um

107

Bh

[264

]B

ohri

um

108

Hs

[277

]H

assi

um

109

Mt

[268

]M

eitn

eriu

m

110

Ds

[271

]D

arm

stad

tium

111

Rg

[272

]R

oent

geni

um

87 Fr[2

23]

Fran

cium

88 Ra

[226

]R

adiu

m

89–1

03

Act

inoi

ds

104

Rf

[261

]R

uthe

rfor

dium

105

Db

[262

]D

ubni

um

106

Sg [266

]Se

abor

gium

1 H1.

008

Hyd

roge

n

Sym

bol o

f el

emen

t

Nam

e of

ele

men

t

PE

RIO

DIC

TA

BL

E O

F T

HE

EL

EM

EN

TS

KE

Y

2 He

4.00

3H

eliu

m

3 Li

6.94

1L

ithiu

m

4 Be

9.01

2B

eryl

lium

Ato

mic

Num

ber

Ato

mic

Wei

ght

79 Au

197.

0G

old

6 C12

.01

Car

bon

8 O16

.00

Oxy

gen

10 Ne

20.1

8N

eon

11 Na

22.9

9So

dium

12 Mg

24.3

1M

agne

sium

14 Si28

.09

Silic

on

16 S32

.07

Sulf

ur

18 Ar

39.9

5A

rgon

19 K39

.10

Pota

ssiu

m

20 Ca

40.0

8C

alci

um

21 Sc44

.96

Scan

dium

22 Ti

47.8

7T

itani

um

23 V50

.94

Van

adiu

m

24 Cr

52.0

0C

hrom

ium

25 Mn

54.9

4M

anga

nese

26 Fe55

.85

Iron

27 Co

58.9

3C

obal

t

28 Ni

58.6

9N

icke

l

29 Cu

63.5

5C

oppe

r

30 Zn

65.4

1Z

inc

32 Ge

72.6

4G

erm

aniu

m

34 Se78

.96

Sele

nium

36 Kr

83.8

0K

rypt

on

37 Rb

85.4

7R

ubid

ium

38 Sr87

.62

Stro

ntiu

m

39 Y88

.91

Yttr

ium

40 Zr

91.2

2Z

irco

nium

41 Nb

92.9

1N

iobi

um

42 Mo

95.9

4M

olyb

denu

m

43 Tc

[97.

91]

Tech

netiu

m

44 Ru

101.

1R

uthe

nium

45 Rh

102.

9R

hodi

um

46 Pd10

6.4

Palla

dium

47 Ag

107.

9Si

lver

48 Cd

112.

4C

adm

ium

50 Sn11

8.7

Tin

52 Te12

7.6

Tellu

rium

54 Xe

131.

3X

enon

55 Cs

132.

9C

aesi

um

56 Ba

137.

3B

ariu

m

57–7

1

Lan

than

oids

72 Hf

178.

5H

afni

um

73 Ta18

0.9

Tant

alum

74 W18

3.8

Tun

gste

n

75 Re

186.

2R

heni

um

76 Os

190.

2O

smiu

m

77 Ir19

2.2

Irid

ium

78 Pt19

5.1

Plat

inum

79 Au

197.

0G

old

80 Hg

200.

6M

ercu

ry

82 Pb20

7.2

Lea

d

84 Po[2

09.0

]Po

loni

um

86 Rn

[222

.0]

Rad

on

Lan

than

oids

57 La

138.

9L

anth

anum

58 Ce

140.

1C

eriu

m

59 Pr14

0.9

Pras

eody

miu

m

60 Nd

144.

2N

eody

miu

m

61 Pm [145

]Pr

omet

hium

62 Sm 150.

4Sa

mar

ium

63 Eu

152.

0E

urop

ium

64 Gd

157.

3G

adol

iniu

m

65 Tb

158.

9Te

rbiu

m

66 Dy

162.

5D

yspr

osiu

m

67 Ho

164.

9H

olm

ium

68 Er

167.

3E

rbiu

m

69 Tm

168.

9T

huliu

m

70 Yb

173.

0Y

tterb

ium

71 Lu

175.

0L

utet

ium

Act

inoi

ds

89 Ac

[227

]A

ctin

ium

90 Th

232.

0T

hori

um

91 Pa23

1.0

Prot

actin

ium

92 U23

8.0

Ura

nium

93 Np

[237

]N

eptu

nium

94 Pu [244

]Pl

uton

ium

95 Am

[243

]A

mer

iciu

m

96 Cm

[247

]C

uriu

m

97 Bk

[247

]B

erke

lium

98 Cf

[251

]C

alif

orni

um

99 Es

[252

]E

inst

eini

um

100

Fm [257

]Fe

rmiu

m

101

Md

[258

]M

ende

levi

um

102

No

[259

]N

obel

ium

103

Lr

[262

]L

awre

nciu

m

For

elem

ents

that

hav

e no

sta

ble

or lo

ng-l

ived

nuc

lides

, the

mas

s nu

mbe

r of

the

nucl

ide

with

the

long

est c

onfi

rmed

hal

f-lif

e is

list

ed b

etw

een

squa

re b

rack

ets.

T

he I

nter

natio

nal U

nion

of

Pure

and

App

lied

Che

mis

try

Peri

odic

Tab

le o

f th

e E

lem

ents

(O

ctob

er 2

005

vers

ion)

is th

e pr

inci

pal s

ourc

e of

dat

a. S

ome

data

may

hav

e be

en m

odif

ied.

2006H I G H E R S C H O O L C E R T I F I C AT E


Chemistry








• Write your Centre Number and Student Number at the top of pages 9, 11, 15, 17, 21 and 25

Total marks – 100


75 marks


Part A – 15 marks



Part B – 60 marks




25 marks



115

Section I 75 marks


Use the multiple-choice answer sheet.

Select the alternative A, B, C or D that best answers the question. Fill in the response ovalcompletely.

Sample: 2 + 4 = (A) 2 (B) 6 (C) 8 (D) 9

A B C D

If you think you have made a mistake, put a cross through the incorrect answer and fill in the new answer.

A B C D

If you change your mind and have crossed out what you consider to be the correct answer, then indicate the correct answer by writing the word correct and drawing an arrow as follows.

correct

A B C D

– 2 –

3

1 Which is the main industrial source of ethylene?

(A) Ethanol

(B) Glucose

(C) Petroleum

(D) Polyethylene

2 Catalysts are required for the production of both ethanol from ethylene and ethylene from ethanol.

Catalyst A ethylene + water ethanol

Catalyst B

What are the identities of Catalyst A and Catalyst B?

(A)

(B)

(C)

(D)

Catalyst A Catalyst B

dilute H+ conc H+

dilute H+ dilute H+

conc H+ conc H+

conc H+ dilute H+

Which set contains only stable nuclei?

2 12 238(A) 1H 6C 92U

16 39 12(B) 8 O 19K 6 C

65 188 24(C) 30 Zn 8O 12 Mg

(D) 146C 16

8O 11H

– 3 –

4 A student used the apparatus shown to determine the molar heat of combustion of ethanol.

Thermometer

Can containing 300 g water

Burner containing ethanol

The following results were obtained.

Initial mass of burner 133.20 g

Final mass of burner 132.05 g

Initial temperature of water 25.0°C

Final temperature of water 45.5°C

What is the molar heat of combustion calculated from this data?

(A) 22.4 kJ mol–1

(B) 25.7 kJ mol–1

(C) 1030 kJ mol–1

(D) 1180 kJ mol–1

5 How many isomers are there for C3H6Cl2?

(A) 3

(B) 4

(C) 5

(D) 6

– 4 –

6 Glucose (C6H12O6) is a monomer that can form naturally occurring polymers.

The approximate atomic weights for the elements which make up glucose are shown in the table.

Element Approximate atomic weight

Carbon 12

Hydrogen 1

Oxygen 16

Using data from the table, what would be the approximate molecular weight of a polymer made from 5 glucose monomers?

(A) 810

(B) 828

(C) 882

(D) 900

7 Which class of compounds typically has a sweet smell?

(A) Esters

(B) Alkenes

(C) Haloalkanes

(D) Alkanoic acids

8 Acid X is 0.1 mol L–1 hydrochloric acid.

Acid Y is 1.0 mol L–1 acetic acid (ethanoic acid).

How does acid X compare with acid Y?

(A) X is weaker and more dilute than Y.

(B) X is stronger and more dilute than Y.

(C) X is weaker and more concentrated than Y.

(D) X is stronger and more concentrated than Y.

– 5 –

9 Which statement best describes the equivalence point in a titration between a strong acid and a strong base?

(A) The point at which the first sign of a colour change occurs

(B) The point at which equal moles of acid and base have been added together

(C) The point at which equal moles of H+ ions and OH– ions have been added together

(D) The point at which the rate of the forward reaction equals the rate of the reverse reaction

10 Phosphorus pentoxide reacts with water to form phosphoric acid according to the following equation.

P2O5(s) + 3H2O(l) → 2H3PO4(aq)

Phosphoric acid reacts with sodium hydroxide according to the following equation.

H3PO4(aq) + 3NaOH(aq) → Na3PO4(aq) + 3H2O(l)

A student reacted 1.42 g of phosphorus pentoxide with excess water.

What volume of 0.30 mol L–1 sodium hydroxide would be required to neutralise all the phosphoric acid produced?

(A) 0.067 L

(B) 0.10 L

(C) 0.20 L

(D) 5.0 L

11 In 1884, Svante Arrhenius proposed a definition for acids. His definition was soon accepted as superior to that put forward by earlier chemists.

Why was Arrhenius’ definition seen as a major improvement?

(A) It explained why some acids do not contain oxygen.

(B) It showed how the solvent can affect the strength of an acid.

(C) It showed the relationship between pH and the concentration of H+ ions.

(D) It could be used to explain why some acids are strong and others are weak.

– 6 –

12 Which statement explains why catalysts are often used in chemical reactions?

(A) Catalysts increase the rate of reactions.

(B) Catalysts increase the yield of products of reactions.

(C) Catalysts increase the purity of products of reactions.

(D) Catalysts increase the activation energies of reactions.

13 Why are microscopic membrane filters useful for water purification?

(A) They can kill bacteria.

(B) They adjust the pH of water to 7.

(C) They are composed of biodegradable polymers.

(D) They can remove very small particles from water.

14 A scientist used atomic absorption spectroscopy (AAS) to analyse the concentration of iron in a sample of water. The scientist analysed the sample five times and obtained the absorbances shown in the table.

Analysis Absorbance

1 0.390

2 0.392

3 0.249

4 0.387

5 0.394

The scientist needed an average absorbance to determine the concentration of iron from a calibration curve.

Which value should the scientist use?

(A) 0.362

(B) 0.3624

(C) 0.39075

(D) 0.391

– 7 –

15 Which graph shows how pressure and temperature affect the yield of ammonia produced by the Haber process?

(A) 80706050403020100

100 200 300 400Pressure (atmosphere)

(B) 80706050403020100


(C) 80706050403020100


(D) 80706050403020100


– 8 –

% y

ield

of

amm

onia

% y

ield

of

amm

onia

%

yie

ld o

f am

mon

ia

% y

ield

of

amm

onia 350°C

400°C

450°C 500°C 550°C

550°C 500°C

450°C 400°C 350°C

500°C

400°C

550°C

350°C

450°C

400°C

500°C

350°C

550°C

450°C








Marks

3


Describe how technology has enabled the transuranic elements to be produced.

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

116 – 9 –

Marks

1

3


(a) Calculate the pH of a 0.2 mol L–1 solution of hydrochloric acid.

...............................................................................................................................

...............................................................................................................................

(b) Calculate the pH after 20 mL of 0.01 mol L–1 sodium hydroxide is added to 50 mL of 0.2 mol L–1 hydrochloric acid. Include a balanced chemical equation in your answer.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

– 10 –





Student Number

Marks

1

3


A student studying the mass change that occurs during fermentation added glucose, water and yeast to a flask and stoppered the flask with some cotton wool.

The student measured the mass of the flask daily for seven days. The table shows the data collected.

Day Mass (g)

1 381.05

2 376.96

3 373.42

4 370.44

5 370.42

6 370.40

7 370.39

(a) Calculate the moles of CO2 released between days 1 and 7.

...............................................................................................................................

...............................................................................................................................

(b) Calculate the mass of glucose that underwent fermentation between days 1 and 7. Include a balanced chemical equation in your answer.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

117 – 11 –

Marks

1

2

2


A student was asked to perform a first-hand investigation to measure the difference in potential of various combinations of metals in an electrolyte solution. The student was provided with three metals: aluminium, zinc and silver; and three electrolyte solutions: aluminium nitrate, zinc nitrate and silver nitrate.

(a) Identify which combination of the metals supplied should give the highest potential difference.

...............................................................................................................................

(b) Sketch and label a diagram of an experimental setup that the student could use with the combination of metals identified in part (a).

(c) Write a balanced chemical equation for the overall reaction for the metals identified in part (a), and calculate the expected potential difference.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................


– 12 –

Marks

2


(d) The measured potential difference obtained varied from the theoretical value.

Outline steps the student could have taken to minimise this variation.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

End of Question 19

– 13 –

BLANK PAGE

– 14 –


XXX118




Student Number

Marks

7


Analyse why ethylene is such an important starting material for the chemical industry. In your answer, include relevant chemical equations, and a description of new materials and fuels that can be prepared from ethylene.

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

– 15 –

Marks

1

2


You performed a first-hand investigation to identify the pH of a range of salt solutions.

(a) Identify an acidic salt you used.

...............................................................................................................................

(b) Explain the acidic nature of the salt you selected. Include a balanced chemical equation in your answer.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

– 16 –





Student Number

Marks

4


The atmosphere contains acidic oxides of sulfur which have been increasing in concentration since the Industrial Revolution.

Discuss the evidence for this statement, and include relevant balanced chemicalequations.

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

118a – 17 –

r d

wyel ow

well w

uol url ss

bl ebl e

ink

Marks

3


Correct swimming pool maintenance requires regular monitoring of the pH level of the water.

(a) Select the best indicator from the graph to check that the pH of swimming pool water lies within the correct range of 7.0 – 7.6. Justify your choice.

redrede yelloyelloy owMethyl orange

yelloyellowl bluuue Bromothymol blue

colo rlescolo rlessc ou e pinkpinkpPhenolphthalein

1 2 3 4 5 6 7 8 9 10 11 12 13

pH

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................


– 18 –

Marks

1

2


(b) Another part of swimming pool maintenance is adjusting chlorine levels in the pool. ‘Liquid chlorine’ is a solution of sodium hypochlorite (NaOCl) which can be used to do this. Upon addition of sodium hypochlorite to the pool, the following equilibrium reaction occurs:

OCl–(aq) + H2O(l) HOCl(aq) + OH–(aq)

(i) State a reason for the regular chlorination of swimming pool water.

...................................................................................................................

...................................................................................................................

(ii) Explain how the addition of sodium hypochlorite will affect the pH of the water in the pool.

...................................................................................................................

...................................................................................................................

...................................................................................................................

...................................................................................................................

End of Question 23

– 19 –

BLANK PAGE

– 20 –





Student Number

Marks

1

4


Early in the twentieth century, Fritz Haber developed a method for preparing ammonia.

(a) Write a balanced chemical equation for the preparation of ammonia using the Haber process.

...............................................................................................................................

(b) Evaluate the significance of Haber’s discovery at that time in world history.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

119 – 21 –

Marks

2


Atomic absorption spectroscopy was used to analyse a set of standard solutions of copper. The results are presented in the table.

Concentration of copper (ppm)

Absorbance

0 0

5 0.20

10 0.39

15 0.52

20 0.64

25 0.77

Abs

orba

nce

(a) Draw an appropriate graph of the data.

1.00

0.80

0.60

0.40

0.20

0 5 10 15 20 25 30 35

Concentration of copper (ppm)


– 22 –

0

Marks

3


(b) An analysis of two samples containing copper was then performed. The results are given in the table.

Sample Absorbance

1 0.44

2 0.90

Use your graph to estimate the concentration of copper present in the samples, and assess the validity of each of your estimates.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

End of Question 25

– 23 –

BLANK PAGE

– 24 –





Student Number

Marks

1

3


The flow diagram shows a series of tests that can be used to identify carbonate, chloride and sulfate ions present in a sample.

Sample

Bubbles observed

Step 1 Add excess HNO3(aq)

Step 2 Add excess Ba2+(aq)

White precipitate forms

Filter off precipitate Step 3 Add Ag+(aq) to the filtrate

White precipitate forms

(a) Identify the gas observed during Step 1.

...............................................................................................................................

(b) Explain why the analysis must be performed in the sequence given.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

119a – 25 –

Marks

1

2

1


One of the most common methods for determining the concentration of metal ions in water samples involves titration with a reagent called EDTA. In alkaline solution EDTA is present as an anion with a 4 – charge. In this form it reacts with metal ions such as calcium and magnesium in a 1 : 1 ratio:

Ca2+ + EDTA4– → Ca(EDTA)2–

When the reaction between the metal ions and EDTA4– is complete, an indicator also present in the solution changes colour.

A student used the following procedure to determine the concentration of calcium in a sample of water:

• 50.0 mL of water sample was pipetted into a conical flask

• 5.0 mL of ammonia/ammonium ion buffer and two drops of indicator were added

• Sample was titrated with 0.0200 mol L–1 EDTA4– until indicator changed colour

• The above procedure was repeated a further three times

• The average volume of EDTA4– used in the four titrations was 24.0 mL

(a) What is the average number of moles of EDTA4– added to reach the end point?

...............................................................................................................................

...............................................................................................................................

(b) The student used the answer to part (a) to calculate the concentration of Ca2+ in the water sample in mg L–1.

What concentration was obtained?

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

(c) The concentration of Ca2+ in the water sample was also determined by atomic absorption spectroscopy, and found to be 16% lower than the value obtained by titration with EDTA4–.

Suggest a reason why the concentration of Ca2+ determined by EDTA titration was higher.

...............................................................................................................................

...............................................................................................................................

– 26 –


The diagram shows recent atmospheric ozone concentrations above Antarctica.

Explain how this information was obtained, and outline the changes that haveoccurred in atmospheric ozone concentrations above Antarctica during the past twentyyears.

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

DobsonUnits

100

500

400

300

200

4

– 27 –

Marks

BLANK PAGE

– 28 –



Chemistry

Section II




Pages

Question 29 Industrial Chemistry ............................................................ 30–31





120 – 29 –

Marks

3

2

1

2

3

7


(a) During your practical work you performed a first-hand investigation to identify the products of electrolysis of sodium chloride.

(i) Outline a risk assessment for this investigation, and show how this would influence the experimental procedure.

(ii) Provide a conclusion based on one set of observations from your first-hand investigation.

(b) The diagram represents how one class of molecules assembles in water to form a structure called a micelle.

Awaiting Copyright Clearance

(i)

(ii)

(iii)

Identify the class of molecules shown.

Account for the formation of a micelle.

Explain what happens when oil is added to water containing these molecules.

(c) In this option you studied one natural product that was not a fossil fuel.

Describe the issues associated with shrinking world supplies of this natural product, and evaluate progress being made to solve the problems identified.


– 30 –

Marks

1

2

4


(d) The diagram summarises the steps in the Contact process.

Oxygen from air

Oxygen from air

Sulfur dioxideX

Sulfur trioxide

Sulfuric acidStep 1 Step 2 Step 3

(i) Identify the starting material, X, for the first step in the Contact process.

(ii) Outline the chemistry involved in the conversion of sulfur trioxide to sulfuric acid.

(iii) Justify the conditions you would use to maximise the rate and yield of the second step in the Contact process. Include a balanced chemical equation in your answer.

End of Question 29

– 31 –

Marks

3

2

1

2

3


(a) During your practical work you performed a first-hand investigation to identify the factors that affect the rate of an electrolysis reaction.



(b) The diagram shows the wreck of an iron ship sitting on the bottom of the ocean at a great depth.

Acidic microenvironment

Ocean water

Sulfate-reducing bacteria microenvironment

Ocean floor

(i) Identify the gas dissolved in water that causes corrosion.

(ii) Outline the effect of temperature and pressure on the solubility of gases in water.

(iii) Microenvironments are localised areas where conditions are different from those in the surrounding areas.

Explain the effect of each microenvironment on the rate of corrosion of the iron ship. Include at least one balanced chemical equation in your answer.


– 32 –

Marks

7

1

2

4


(c) The diagram shows artefacts recovered from a shipwreck.

Wooden chest Encrusted copper coins Lead cannon balls

Describe how these artefacts may have been affected by prolonged exposure to the marine environment, and analyse the role of chemistry in procedures used for restoration of such objects.

(d) The diagram shows that iron is an important construction material for an oil rig.


(i) Identify the name for alloys composed of iron and carbon.

(ii) Outline the process of rusting.

(iii) Describe TWO methods for preventing corrosion of iron, and assess their suitability for use in different parts of the oil rig.

End of Question 30

– 33 –

Marks

3

2

1

2

3


(a) During your practical work you performed a first-hand investigation to observe the effect of changes in pH and temperature on the reaction of an enzyme.



(b) (i) Identify the part of the cell where glycolysis occurs.

(ii) The diagram shows ATP which is used in many metabolic processes.

NH2

C N N C

C − H C C

O− O− O− H N N

−O P O P O P O CH2 O

O O O

H H H H

OH OH

Account for the widespread use of ATP in metabolism.

(iii) Enzymes usually show a high degree of substrate specificity in the reactions they catalyse.

Explain how this specificity is achieved.


– 34 –

Question 31 (continued) Marks

7 (c) Increased understanding of how the body produces energy has led to a number of weight loss diets. Several of these promote a diet low in carbohydrates. The diagram summarises how two of the food groups used by the body are metabolised to produce energy.

Fats Carbohydrates

Food

Acetyl CoA

TCA cycle

Oxidative phosphorylation

Describe how carbohydrates and fats are metabolised to produce energy, and explain how a diet low in carbohydrates might lead to weight loss.


– 35 –

Marks

1

2

4


(d) The diagram represents the structure of a relaxed skeletal muscle cell.


(i)

(ii)

(iii)

Identify the class of molecules to which myosin and actin belong.

Contrast the appearance and function of type 1 and type 2 skeletal muscle cells.

Describe how muscle contractions occur, and explain how a contraction would change the appearance of the muscle cell in the diagram above.

End of Question 31

– 36 –

Marks

3

2

1

2

3

7


(a) During your practical work you performed a first-hand investigation to gather information about the oxidising strength of KMnO4.



(b) (i) Identify a pigment commonly used in an ancient culture, such as early Egyptian or Roman.

(ii) The diagram shows the absorption spectrum of a pigment used in a painting found inside an ancient Egyptian tomb.

Abs

orba

nce

Violet Blue Green Orange Red0.0

1.0

400 500 600

Wavelength, nm

700 800

Use the spectrum to identify the colour of this pigment. Justify your choice.

(iii) Explain why many minerals containing transition metal ions have been used as pigments.

(c) Evaluate the contributions of Bohr, Pauli and Hund in developing our current understanding of the arrangement of electrons around the nuclei of atoms.


– 37 –

Marks

1

2

4


(d) (i) Name the block in the Periodic Table occupied by the transition metals.

(ii) Account for the observation that some transition metal complex ions can act as strong oxidising agents.

(iii) The formulae of a number of complex ions are shown.

[Cu(H2O)6]2+

[Fe(CN)6]4–

[Co(NH3)4Cl2]+

[Ni(H2O)6]2+

[Fe(H2O)4Cl2]+

Identify a feature of all ligands that enables them to form bonds to metal ions, and explain the bonding in one of the above complex ions. Include a Lewis diagram in your answer.

End of Question 32

– 38 –

Marks

3

2

1

2

3

7


(a) During your practical work you performed a first-hand investigation using flame tests and/or spectroscope analysis to identify and describe the emission spectra of elements including sodium and mercury.



(b) Carbohydrates are a general class of compounds that includes monosaccharides such as glucose, and polysaccharides such as glycogen and cellulose.

(i) What is the general formula of carbohydrates?

(ii) Compare the composition of glycogen and cellulose, and where they occur in nature.

(iii) Explain the differences in structure between glycogen and cellulose.

(c) The diagram shows a crime scene where there has been a fire. No identification was found on the body. A small amount of residue was extracted from the tin for analysis.

Describe TWO modern forensic chemistry techniques that could be used to examine evidence from this crime scene, and analyse why these techniques are suitable for forensic investigations.


– 39 –

C

O

OH

A

Question 33 (continued) Marks

1

2

4

(d) The structure of the amino acid glycine is shown.

N

H

H

C

H

H

(i) Identify the functional group A.

(ii) Use structural formulae to write a balanced chemical equation to show the formation of a dipeptide containing two glycine molecules.

(iii) The amino acid sequences of two proteins are shown.

Protein A Cysteine – Tyrosine – Isoleucine – Glutamine – Asparagine – Cysteine – Proline – Leucine – Glycine

Protein B Cysteine – Tyrosine – Phenylalanine – Glutamine – Asparagine – Cysteine – Proline – Arginine – Glycine

Describe a chemical test for proteins, and explain how enzymes could be used to distinguish between Proteins A and B.

End of paper

– 40 –



Chemistry

DATA SHEET


Volume of 1 mole ideal gas: at 100 kPa andat 0°C (273.15 K) ...................... 22.71 Lat 25°C (298.15 K) .................... 24.79 L

Ionisation constant for water at 25°C (298.15 K), Kw ................. 1.0 × 10–14


Some useful formulae pH = –log10[H+] ΔH = –m C ΔT

Some standard potentials –K+ + e K(s) –2.94 V

Ba2+ + 2e– Ba(s) –2.91 V

Ca2+ + 2e– Ca(s) –2.87 V

–Na+ + e Na(s) –2.71 V

Mg2+ + 2e– Mg(s) –2.36 V

Al3+ + 3e– Al(s) –1.68 V

Mn2+ + 2e– Mn(s) –1.18 V

H2O + e– –1 H (g) OH– 2 2 + –0.83 V

Zn2+ + 2e– Zn(s) –0.76 V

Fe2+ + 2e– Fe(s) –0.44 V

Ni2+ + 2e– Ni(s) –0.24 V

Sn2+ + 2e– Sn(s) –0.14 V

Pb2+ + 2e– Pb(s) –0.13 V

–H+ + e –12 H2(g) 0.00 V

SO42– + 4H+ + 2e– SO2(aq) + 2H2O 0.16 V

Cu2+ + 2e– Cu(s) 0.34 V

–12 O2(g) + H2O + 2e– 2OH– 0.40 V

–Cu+ + e Cu(s) 0.52 V

–12 I2(s) + e– I– 0.54 V

–12 I2(aq) + e– I– 0.62 V

–Fe3+ + e Fe2+ 0.77 V

–Ag+ + e Ag(s) 0.80 V

–12 Br2(l) + e– Br– 1.08 V

–12 Br2(aq) + e– Br– 1.10 V

–12 O2(g) + 2H+ + 2e– H2O 1.23 V

–12 Cl2(g) + e– Cl– 1.36 V

–12 Cr2O72– + 7H+ + 3e– Cr3+ + –72 H2O 1.36 V

–12 Cl2(aq) + e– Cl– 1.40 V

–MnO4 + 8H+ + 5e– Mn2+ + 4H2O 1.51 V

–12 F2(g) + e– F– 2.89 V

Aylward and Findlay, SI Chemical Data (5th Edition) is the principal source of data for

120a this examination paper. Some data may have been modified for examination purposes.

– 41 –

– 42 –

9 F19

.00

Fluo

rine

17 Cl

35.4

5C

hlor

ine

35 Br

79.9

0B

rom

ine

53 I12

6.9

Iodi

ne

85 At

[210

.0]

Ast

atin

e

7 N14

.01

Nitr

ogen

15 P30

.97

Phos

phor

us

33 As

74.9

2A

rsen

ic

51 Sb12

1.8

Ant

imon

y

83 Bi

209.

0B

ism

uth

5 B10

.81

Bor

on

13 Al

26.9

8A

lum

iniu

m

31 Ga

69.7

2G

alliu

m

49 In11

4.8

Indi

um

81 Tl

204.

4T

halli

um

107

Bh

[264

.1]

Boh

rium

108

Hs

[277

]H

assi

um

109

Mt

[268

]M

eitn

eriu

m

110

Ds

[271

]D

arm

stad

tium

111

Rg

[272

]R

oent

geni

um

87 Fr[2

23.0

]Fr

anci

um

88 Ra

[226

.0]

Rad

ium

89–1

03

Act

inid

es

104

Rf

[261

.1]

Rut

herf

ordi

um

105

Db

[262

.1]

Dub

nium

106

Sg[2

66.1

]Se

abor

gium

57 La

138.

9L

anth

anum

89 Ac

[227

.0]

Act

iniu

m

1 H1.

008

Hyd

roge

n

Sym

bol o

f el

emen

t

Nam

e of

ele

men

t

PE

RIO

DIC

TA

BL

E O

F T

HE

EL

EM

EN

TS

KE

Y

2 He

4.00

3H

eliu

m

3 Li

6.94

1L

ithiu

m

4 Be

9.01

2B

eryl

lium

Ato

mic

Num

ber

Ato

mic

Wei

ght

79 Au

197.

0G

old

6 C12

.01

Car

bon

8 O16

.00

Oxy

gen

10 Ne

20.1

8N

eon

11 Na

22.9

9So

dium

12 Mg

24.3

1M

agne

sium

14 Si28

.09

Silic

on

16 S32

.07

Sulf

ur

18 Ar

39.9

5A

rgon

19 K39

.10

Pota

ssiu

m

20 Ca

40.0

8C

alci

um

21 Sc44

.96

Scan

dium

22 Ti

47.8

7T

itani

um

23 V50

.94

Van

adiu

m

24 Cr

52.0

0C

hrom

ium

25 Mn

54.9

4M

anga

nese

26 Fe55

.85

Iron

27 Co

58.9

3C

obal

t

28 Ni

58.6

9N

icke

l

29 Cu

63.5

5C

oppe

r

30 Zn

65.4

1Z

inc

32 Ge

72.6

4G

erm

aniu

m

34 Se78

.96

Sele

nium

36 Kr

83.8

0K

rypt

on

37 Rb

85.4

7R

ubid

ium

38 Sr87

.62

Stro

ntiu

m

39 Y88

.91

Yttr

ium

40 Zr

91.2

2Z

irco

nium

41 Nb

92.9

1N

iobi

um

42 Mo

95.9

4M

olyb

denu

m

43 Tc

[97.

91]

Tech

netiu

m

44 Ru

101.

1R

uthe

nium

45 Rh

102.

9R

hodi

um

46 Pd10

6.4

Palla

dium

47 Ag

107.

9Si

lver

48 Cd

112.

4C

adm

ium

50 Sn11

8.7

Tin

52 Te12

7.6

Tellu

rium

54 Xe

131.

3X

enon

55 Cs

132.

9C

aesi

um

56 Ba

137.

3B

ariu

m

57–7

1

Lan

than

ides

72 Hf

178.

5H

afni

um

73 Ta18

0.9

Tant

alum

74 W18

3.8

Tun

gste

n

75 Re

186.

2R

heni

um

76 Os

190.

2O

smiu

m

77 Ir19

2.2

Irid

ium

78 Pt19

5.1

Plat

inum

79 Au

197.

0G

old

80 Hg

200.

6M

ercu

ry

82 Pb20

7.2

Lea

d

84 Po[2

09.0

]Po

loni

um

86 Rn

[222

.0]

Rad

on

58 Ce

140.

1C

eriu

m

59 Pr14

0.9

Pras

eody

miu

m

60 Nd

144.

2N

eody

miu

m

61 Pm[1

44.9

]Pr

omet

hium

62 Sm 150.

4Sa

mar

ium

63 Eu

152.

0E

urop

ium

64 Gd

157.

3G

adol

iniu

m

65 Tb

158.

9Te

rbiu

m

66 Dy

162.

5D

yspr

osiu

m

67 Ho

164.

9H

olm

ium

68 Er

167.

3E

rbiu

m

69 Tm

168.

9T

huliu

m

70 Yb

173.

0Y

tterb

ium

71 Lu

175.

0L

utet

ium

90 Th

232.

0T

hori

um

91 Pa23

1.0

Prot

actin

ium

92 U23

8.0

Ura

nium

93 Np

[237

.0]

Nep

tuni

um

94 Pu[2

44.1

]Pl

uton

ium

95 Am

[243

.1]

Am

eric

ium

96 Cm

[247

.1]

Cur

ium

97 Bk

[247

.1]

Ber

keliu

m

98 Cf

[251

.1]

Cal

ifor

nium

99 Es

[252

.1]

Ein

stei

nium

100

Fm[2

57.1

]Fe

rmiu

m

101

Md

[258

.1]

Men

dele

vium

102

No

[259

.1]

Nob

eliu

m

103

Lr

[262

.1]

Law

renc

ium

Act

inid

es

Lan

than

ides

Whe

re th

e at

omic

wei

ght i

s no

t kno

wn,

the

rela

tive

atom

ic m

ass

of th

e m

ost c

omm

on r

adio

activ

e is

otop

e is

sho

wn

in b

rack

ets.

The

ato

mic

wei

ghts

of

Np

and

Tc

are

give

n fo

r th

e is

otop

es 23

7 Np

and

99T

c.






• Board-approved calculators maybe used

• A data sheet and a Periodic Tableare provided at the back of thispaper

• Write your Centre Number andStudent Number at the top ofpages 13, 15, 17, and 21

Total marks – 100

Pages 2–24

75 marks


Part A – 15 marks



Part B – 60 marks



Pages 25–36

25 marks



Section II

Section I

Chemistry

115



– 2 –

Section I75 marks

Part A – 15 marksAttempt Questions 1–15Allow about 30 minutes for this part



Sample: 2 + 4 = (A) 2 (B) 6 (C) 8 (D) 9

A B C D

If you think you have made a mistake, put a cross through the incorrect answer and fill in thenew answer.

A B C D

If you change your mind and have crossed out what you consider to be the correct answer, thenindicate the correct answer by writing the word correct and drawing an arrow as follows.

correct

A B C D

1 Which of the following conditions would produce a radioactive isotope?

(A) Too many atoms in the sample provided

(B) Too many protons and neutrons in the atom

(C) Too many electrons in the outer shell of the atom

(D) Too many electrons for the number of neutrons in the atom

2 Which of the following makes cellulose a potential raw material for the petrochemicalindustry?

(A) It is available in many parts of the world.

(B) It is light in weight and easy to transport.

(C) It is an organic polymer based on carbon.

(D) It is a polymer that undergoes combustion.

3 The heat of combustion of butan-1-ol is 2676 kJ mol−1.

What is the value of the heat of combustion in kJ g−1?

(A) 30.41

(B) 36.10

(C) 44.60

(D) 47.79

– 3 –

4 Terylene (polyester) is a condensation polymer. Part of the structure of the polymer isshown.

What are the two monomers that form this polymer?

Monomer 1 Monomer 2

HO

H

C

H

H

C OH

H

HO

O

C

O

C OH

HO

O

C

O

C OH

H HH O

O

C H

HO OH

H

C

H

C

HO

H

C

H

H

C OH

H

H H

(A)

(B)

(C)

(D)

O

O

C

O

C O

H

C

H

H

C O

O

C

H

O

C O

H

C

H

H

C

H

– 4 –

5 An electrochemical cell is set up as shown in the diagram.

What are two observations for this electrochemical cell?

6 Which of the following is a common use for ethyl pentanoate?

(A) Flavouring

(B) Fuel

(C) Indicator

(D) Solvent

Observation 2

In Beaker 2 the solution becamea darker blue

A reddish precipitate formed onthe copper electrode

In Beaker 2 the solution becamea darker blue

A reddish precipitate formed onthe copper electrode

Observation 1

A reading was shown on thevoltmeter

In Beaker 2 the blue solutionfaded

A grey precipitate formed onthe aluminium electrode

Electrons moved through thevoltmeter

(A)

(B)

(C)

(D)

V

salt bridge

Beaker 1 Beaker 2

Al(s)

Al3+(aq)

Cu(s)

Cu2+(aq)

– 5 –

7 A series of observations was made about a first-hand investigation.

• A cup of carbonated soft drink was poured from a newly-opened, chilled bottle.

• A lot of bubbles were observed in the cup.

• The cup was then left on the kitchen bench for several hours.

• After this time, it was observed that there were no bubbles visible in the cup.

Why were there no bubbles visible in the cup after several hours?

(A) The bubbles of carbon dioxide had dissolved into the soft drink.

(B) The carbon dioxide had been neutralised by the water in the soft drink.

(C) Carbon dioxide is less soluble at higher temperatures and lower pressures.

(D) Carbon dioxide is more soluble at higher temperatures and lower pressures.

8 What would be the pH of a 0.1 mol L−1 solution of sulfuric acid?

(A) Less than 1.0

(B) Exactly 1.0

(C) Between 1.0 and 7.0

(D) Greater than 7.0

9 Which of the following pairs would form a buffer solution?

(A) HCl(aq) / Cl−(aq)

(B) H2PO4−(aq) / PO4

3−(aq)

(C) H2SO4(aq) / HSO4−(aq)

(D) CH3COOH(aq) / CH3COO−(aq)

– 6 –

10 A titration was conducted by adding NaOH from a teflon-coated burette to HCl in aconical flask. The pH in the flask was recorded during the titration and Curve A wasproduced.

The table shows appropriate indicators used to identify the equivalence point in titrations.For NaOH and HCl the appropriate indicator is bromothymol blue.

A second titration was conducted by adding NaOH to a different acid. The pH in the flaskwas recorded during the titration and Curve B was produced.

What is the appropriate indicator for Curve B using the table?

(A) Methyl orange

(B) Methyl red

(C) Cresolphthalein

(D) Alizarin yellow

Curve B14

7pH

00 10 20

Volume of NaOH added (mL)

30 40

Basic colour

yellow

yellow

blue

red

red

Range of colour change

3.1 – 4.4

4.4 – 6.2

6.0 – 7.6

8.1 – 9.7

10.1 – 12.0

Acidic colour

red

red

yellow

colourless

yellow

Indicator

Methyl orange

Methyl red

Bromothymol blue

Cresolphthalein

Alizarin yellow

Curve A

Volume of NaOH added (mL)

pH

14

7

00 10 20 30 40

– 7 –

11 Which of the following substances is best analysed by atomic absorption spectroscopy(AAS)?

(A) Calcium

(B) Iodine

(C) Nitrogen

(D) Silicon

12 A student performed a sampling technique as part of a first-hand investigation on waterquality and repeated the sampling technique several times.

What aspect of the experiment was improved by repeating the procedure?

(A) Accuracy

(B) Reliability

(C) Safety

(D) Validity

13 What is the name of the following compound?

(A) 1,2-difluoro-1-chloroethane

(B) 1,2-difluoro-2-chloroethane

(C) 1-chloro-1,2-difluoroethane

(D) 2-chloro-1,2-difluoroethane

H

F

C

H

F

C H

Cl

– 8 –

14 Water quality analyses were performed at different sites on a river shown on the map.

Map

The table shows the results of the tests performed at the different sites.

Where was each set of tests performed?

Town

Site 3

Site 3

Site 2

Site 1

Limestone quarry

Site 1

Site 2

Site 3

Site 3

River source

Site 2

Site 1

Site 1

Site 2

(A)

(B)

(C)

(D)

Results of tests performed

1

2

3

Site

3

10

7

Dissolved oxygen (ppm)

145

2

12

Biochemical oxygendemand (ppm)

5.2

6.9

7.4

pH

Riversource

Limestonequarry

Town

50 km

River

– 9 –

15 The Winkler method is used to determine the amount of dissolved oxygen in a sample.In this procedure, oxygen reacts with Mn2+ under alkaline conditions to produce aprecipitate of MnO(OH)2.

2Mn2+(aq) + O2(aq) + 4OH−(aq) → 2MnO(OH)2(s)

The precipitate is then dissolved in acid and reacted with iodide, forming iodine andMn2+.

MnO(OH)2(s) + 2Ι−(aq) + 4H+(aq) → I2(aq) + Mn2+(aq) + 3H2O(aq)

Finally, the amount of iodine produced is determined by reaction with thiosulfate.

I2(aq) + 2S2O32−(aq) → 2Ι−(aq) + S4O6

2−(aq)

When a sample of water was analysed using the Winkler method, a total of 0.60 mol ofthiosulfate was used in the reaction.

How many moles of oxygen were present in the original sample?

(A) 0.15

(B) 0.30

(C) 0.60

(D) 1.20

– 10 –

BLANK PAGE

– 11 –

BLANK PAGE


– 12 –


Chemistry


Part B – 60 marksAttempt Questions 16–27Allow about 1 hour and 45 minutes for this part



MarksQuestion 16 (5 marks)

During your practical work you performed a first-hand investigation to distinguishbetween an alkene and the corresponding alkane.

(a) Name the alkene used in your investigation.

...............................................................................................................................

(b) Identify a potential hazard in your investigation, and outline how you addressedthis hazard.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

(c) Outline the procedure you used for your first-hand investigation.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

2

2

1

– 13 –116

Centre Number

Student Number


The heat of combustion of ethanol is 1367 kJ mol–1. In a first-hand investigation todetermine the heat of combustion of ethanol, the experimental value determineddiffered from the theoretical value.

(a) Identify a reason for this difference.

...............................................................................................................................

...............................................................................................................................

(b) Calculate the theoretical mass of ethanol required to heat 200 mL of water from21.0°C to 45.0°C.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................


Assess the impact of the recent development of a named biopolymer on society andthe environment.

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

4

2

1

– 14 –

Marks



Chemistry



You have studied one of the cells shown below.

Cell X Cell Y

Choose ONE of the cells and answer parts (a) and (b).

(a) State ONE environmental impact associated with the cell you have chosen.

...............................................................................................................................

...............................................................................................................................

(b) Describe the chemistry of the cell you have chosen.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

3

1

– 15 –117

Centre Number

Student Number


The flow chart shows a series of steps involved in the production of ethyl butanoate.

→ → →

Describe the chemistry and procedure involved in each of these steps, using diagramswhere appropriate.

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

ethyl butanoatepure ethanolmixture containing ethanolglucose

7

– 16 –

Marks



Chemistry



Analyse how knowledge of the composition and properties of acids has led to changesin the definition of acids.

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

5

– 17 –118

Centre Number

Student Number


A student carried out a first-hand investigation to identify the relationship between themass of a metal used in a reaction, and the volume of gas produced. The first-handinvestigation was carried out at 25°C, and 100 kPa. In each experiment, 200 mL ofhydrochloric acid was added to some zinc, and the volume of gas produced wasrecorded. The diagram shows the equipment used, and the table contains the student’sresults.

(a) Graph the results from these experiments.


3

200 mL HCl(aq)

Zinc

Freely slidingpiston

Volume of gascollected at 25°Cand 100 kPa (mL)

45

125

115

315

365

380

380

380

Mass of zinc(g)

0.12

0.33

0.56

0.83

0.96

1.22

1.64

1.93

– 18 –

Marks


(b) Predict the volume of gas that would be produced in this experiment if 3.00 g ofzinc had been used. Justify your answer.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

(c) Calculate the theoretical volume of gas produced at 25°C and 100 kPa by thereaction of 0.56 g of zinc with the 200 mL of hydrochloric acid.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................


(a) What causes incomplete combustion?

...............................................................................................................................

...............................................................................................................................

(b) Write a balanced equation for the incomplete combustion of methane.

...............................................................................................................................

1

1

2

2

– 19 –

Marks


An antacid tablet is known to contain calcium carbonate (CaCO3). To determine themass of calcium carbonate in the tablet, the following procedure was used.

• The tablet was crushed and then placed in a beaker.

• A pipette was used to add 25.0 mL of 0.600 mol L–1 hydrochloric acid to thecrushed tablet in the beaker.

• Once the reaction between the calcium carbonate and hydrochloric acid hadstopped, phenolphthalein indicator was added to the reaction mixture.

• A teflon-coated burette was then used to add 0.100 mol L–1 sodiumhydroxide to the beaker to neutralise the excess hydrochloric acid.

• The phenolphthalein changed from colourless to pink after 14.2 mL of thesodium hydroxide solution had been added.

(a) Write a balanced chemical equation for the reaction that occurred between thecalcium carbonate in the tablet and the hydrochloric acid.

...............................................................................................................................

(b) How many moles of hydrochloric acid were added to the tablet?

...............................................................................................................................

...............................................................................................................................

(c) Calculate the mass of calcium carbonate in the original antacid tablet.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

3

1

1

– 20 –

Marks



Chemistry



A student collected a 500 mL sample of water from a local creek for analysis. It wasfiltered and the filtrate evaporated to dryness. The following data were collected.

(a) Calculate the percentage of total dissolved solids in the creek sample.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

(b) It is suspected that lead has contaminated the creek. Describe a chemical testthat could be carried out on the water sample to determine the presence of lead.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

(c) The concentrations of ions in substances used by society need to be monitored.Justify this statement with reference to ONE ion you have studied.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

2

2

2

0.16 g

0.19 g

45.33 g

45.59 g

Mass of filter paper

Mass of filter paper and solid

Mass of evaporating basin

Mass of basin and solid remaining

– 21 –119

Centre Number

Student Number


The map shows the catchment for a town water supply.


Dam

Vegetablepatch

Logged native forest

Undisturbednative forest

Undisturbedpine forest

Lake

Town

MAP NOTTO SCALE

Farm

Water supplypipe

– 22 –


Describe TWO possible sources of contamination in this catchment, and assessmethods that could be used for purifying the water before it reaches the town.

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

End of Question 26

7

– 23 –

Marks


The graph shows the variation in concentrations of reactants and product with time forthe Haber process.

(a) State why the concentrations of reactants and product do not change between T1and T2.

...............................................................................................................................

...............................................................................................................................

(b) At time T2 the volume of the reaction vessel was reduced.

(i) Sketch on the graph how the concentrations of reactants and productwould change after the volume was reduced.

(ii) Explain the changes shown on your graph.

...................................................................................................................

...................................................................................................................

...................................................................................................................

...................................................................................................................

...................................................................................................................

...................................................................................................................

2

2

1

hydrogen

nitrogen

ammonia

TimeT1 T2

Molar concentration

– 24 –

Marks



Chemistry

Section II

25 marksAttempt ONE question from Questions 28–32Allow about 45 minutes for this section



Pages






– 25 –120


(a) Sulfuric acid is an important industrial chemical. One of the intermediateproducts in the synthesis of sulfuric acid is H2S2O7.

(i) What is the name of H2S2O7?

(ii) With reference to the properties of sulfuric acid, describe safetyprecautions necessary for its transport.

(b) Nitrogen dioxide forms an equilibrium mixture with dinitrogen tetraoxide asshown.

2NO2(g) N2O4(g)

At 100°C, K for this reaction is 2.08.

At 25°C, a 1.00 L vessel initially contained 0.132 mol of NO2(g). Onceequilibrium had been established, there was 0.0400 mol of N2O4(g) in thevessel.

(i) Explain the effects of the addition of a catalyst and an increase inpressure on the yield of N2O4 in this reaction when carried out at 25°C.

(ii) Calculate the equilibrium constant for this reaction at 25°C, and accountfor any difference from the K value at 100°C.

(c) Advances in chemistry have impacted on the development of technologies.

Discuss this statement by analysing changes that have occurred in industrialmethods for the production of sodium hydroxide.


7

4

2

3

1

– 26 –

Marks


(d) The diagram summarises the Solvay process.

(i) Identify compound X.

(ii) During the Solvay process, ammonia is recovered.

Outline the chemistry involved in the recovery of ammonia, and suggesta reason why this recovery is desirable.

(iii) Identify possible environmental issues that may arise from the Solvayprocess, and evaluate methods of dealing with those environmentalissues.

End of Question 28

5

2

1

carbondioxide

brine

ammonia

limestone

Carbonating tower

sodiumbicarbonate

ammoniumchloride

ammonia

Heatingkiln

carbondioxide

X

calciumchloride

– 27 –

Marks


(a) (i) Reactive metals such as aluminium and zinc form a strongly adheringoxide coating as a result of the reaction with oxygen.

What name is given to these metals?

(ii) The hulls of modern ships contain steels that have lower levels of carbonand sulfur than was used in the past.

Compare the properties and uses of TWO types of steel that you havestudied.

(b) (i) Outline ONE factor that influences the rate of corrosion of iron indeep-water wrecks.

(ii) A student set up a laboratory experiment in which a beaker contained astrip of magnesium, an iron nail, and a solution of iron(II) sulfate andmagnesium sulfate. This was left for several days.

Describe what would happen in this experiment. Include relevantchemical equations in your answer.


Magnesium

Iron nail

Magnesium sulfate/iron(II) sulfate solution

4

2

3

1

– 28 –

Marks


(c) Advances in chemistry have impacted on the development of technologies.

Discuss this statement by analysing current methods of corrosion protection forships.

(d) An iron cannon was recovered from a wreck on the Great Barrier Reef.

The process used to restore the cannon was as follows:

Step 1: The cannon was placed in dilute sodium hydroxide for severalweeks. During this period, the solution was replaced by freshdilute sodium hydroxide solution at regular intervals.

Step 2: Coral that had grown on the cannon was carefully chippedaway.

Step 3: Electrolysis was performed on the cannon.

Step 4: The restored cannon was then coated in wax.

(i) Why was the restored cannon coated in wax?

(ii) Explain the purpose of Step 1 in the restoration of the iron cannon.

(iii) Describe and justify the procedure for Step 3. Include relevant chemicalequations in your answer.

End of Question 29

5

2

1

7

– 29 –

Marks

Reproduced with the permission of the Museum of New Zealand Te Papa Tonarewa


(a) (i) Draw the structure of glycerol.

(ii) Explain the viscosity of glycerol and its solubility in water.

(b) The diagram below summarises some of the steps involved in respiration.

(i) Compare the energy output from glycolysis with the total energy outputfrom respiration.

(ii) Explain the role of oxidation and reduction in respiration.


4

2

Glycolysis

glucose andother sugars

pyruvic acid

acetyl-CoA

TCACycle

Oxidative phosphorylation

CO2, 2H+

O2 H2O

C6

C5

C4

CO2, 2H+

3

1

– 30 –

Marks


(c) A diagram illustrating the structure of a protein is shown.

Describe how chemical features affect the structure and shape of proteins, andassess the importance of shape in the current model of enzyme function.


7

H3N

+

–(CH

2 )4 NH

3 +COO−

––CH

2 –S–S–CH

2 ––

–CH

CH

2 CH

3

CH

3

CH

–

CH

3

CH

3

OCH2

CH2C−NH

H HO

CO

HN

CH2

OH O C

O

−OC

CH

2 –

– 31 –

Marks


(d) An athletics coach persuaded his runners to drink one of two sports drinksimmediately before a race to boost performance. The composition of the twodrinks is shown in the table. The coach believes that the sports drinks will givethe runners extra energy during both a sprint race and a marathon.

*Maltodextrin is a polymer composed of many glucose molecules bonded together.

(i) Define the term carbohydrate.

(ii) Describe the chemical process involved when humans storecarbohydrates for later use.

(iii) Use data in the table to assess the hypothesis made by the coach.

End of Question 30

5

2

1

Sodium(mg per 500 mL)

225

130

Carbohydratecomposition

sucroseglucosefructose

fructosemaltodextrin*

Carbohydratecontent (%)

6

8

Name of sportsdrink

Athletaid

Energade

– 32 –

Marks


(a) A solution of iron(II) sulfate is mixed with a solution of potassiumpermanganate under acidic conditions, resulting in a colour change.

(i) What is the observed colour change?

(ii) Account for the colour change in terms of oxidation states. Includerelevant half-equations in your answer.

(b) The table provides examples of the colours shown by transition metal complexes.

(i) Account for the differences in colours shown by these transition metalcomplexes.

(ii) Assess the importance of minerals as pigments to TWO ancient cultures.

(c) Describe the methodology and use of laser microspectral analysis, and assessthe impact of advances in the understanding of emission spectra on thedevelopment of technologies.


7

4

2

Colour of complex

light blue

dark blue

green

violet

Ligand

H2O

NH3

H2O

H2O

Metal ion

Cu2+

Cu2+

Cr3+

Cr2+

3

1

– 33 –

Marks


(d) (i) Define the Pauli exclusion principle.

(ii) Distinguish between first ionisation energy and electronegativity.

(iii) The graph shows the first ionisation energies for the elements helium toneon.

Analyse the relationship between first ionisation energy and electronconfiguration, using data from the graph.

End of Question 31

2500

2000

1500

1000

500

0He Li Be B C N O F Ne

First ionisation

energy(kJ mol–1)

5

2

1

– 34 –

Marks


(a) The diagram shows the emission spectra of three elements and an unknownmixture.

(i) Name TWO elements present in the unknown mixture.

(ii) Describe how emission spectra assist in the identification of elements ina mixture.

(b) The diagram illustrates the structure of DNA.

(i) Identify the components labelled X, Y and Z.

(ii) Explain how the analysis of DNA allows for identification ofrelationships between people.

(iii) Discuss the ethics of maintaining data banks of DNA.


3

2

1

X

Y

Z

3

1

Unknown mixture

As

Na

Pb

– 35 –

Marks

Reproduced with the permission of Dr Alan J, Jircitano


(c) Describe the structure and composition of proteins, and assess the potential ofelectrophoresis as a method for their analysis.

(d) (i) What type of carbohydrate is sucrose?

(ii) Describe a chemical test that can be used to distinguish glucose fromstarch.

(iii) A scientist wanted to develop a method of separation for a mixture of sixcarbohydrates using high performance liquid chromatography. Thediagram shows the chromatograms obtained for the mixture using twodifferent solvents as the mobile phase.

Describe high performance liquid chromatography, and assess theeffectiveness of the different solvents used by the scientist for separatingthe mixture of carbohydrates.

End of paper

5

2

1

7

– 36 –

Marks



– 37 –

DATA SHEET





Some useful formulaepH = –log10[H+] ∆H = –m C ∆T



Chemistry

Aylward and Findlay, SI Chemical Data (5th Edition) is the principal source of data forthis examination paper. Some data may have been modified for examination purposes.120a

K+ + e– K(s) –2.94 V

Ba2+ + 2e– Ba(s) –2.91 V

Ca2+ + 2e– Ca(s) –2.87 V

Na+ + e– Na(s) –2.71 V

Mg2+ + 2e– Mg(s) –2.36 V

Al3+ + 3e– Al(s) –1.68 V

Mn2+ + 2e– Mn(s) –1.18 V

H2O + e– 1–2 H2(g) + OH– –0.83 V

Zn2+ + 2e– Zn(s) –0.76 V

Fe2+ + 2e– Fe(s) –0.44 V

Ni2+ + 2e– Ni(s) –0.24 V

Sn2+ + 2e– Sn(s) –0.14 V

Pb2+ + 2e– Pb(s) –0.13 V

H+ + e– 1–2 H2(g) 0.00 V

SO42– + 4H+ + 2e– SO2(aq) + 2H2O 0.16 V

Cu2+ + 2e– Cu(s) 0.34 V

1–2 O2(g) + H2O + 2e– 2OH– 0.40 V

Cu+ + e– Cu(s) 0.52 V

1–2 I2(s) + e– I– 0.54 V

1–2 I2(aq) + e– I– 0.62 V

Fe3+ + e– Fe2+ 0.77 V

Ag+ + e– Ag(s) 0.80 V

1–2 Br2(l) + e– Br– 1.08 V

1–2 Br2(aq) + e– Br– 1.10 V

1–2 O2(g) + 2H+ + 2e– H2O 1.23 V

1–2 Cl2(g) + e– Cl– 1.36 V

1–2 Cr2O72– + 7H+ + 3e– Cr3+ + 7–2 H2O 1.36 V

1–2 Cl2(aq) + e– Cl– 1.40 V

MnO4– + 8H+ + 5e– Mn2+ + 4H2O 1.51 V

1–2 F2(g) + e– F– 2.89 V

– 38 –

9 F19

.00

Fluo

rine

17 Cl

35.4

5C

hlor

ine

35 Br

79.9

0B

rom

ine

53 I12

6.9

Iodi

ne

85 At

[210

.0]

Ast

atin

e

7 N14

.01

Nitr

ogen

15 P30

.97

Phos

phor

us

33 As

74.9

2A

rsen

ic

51 Sb12

1.8

Ant

imon

y

83 Bi

209.

0B

ism

uth

5 B10

.81

Bor

on

13 Al

26.9

8A

lum

iniu

m

31 Ga

69.7

2G

alliu

m

49 In11

4.8

Indi

um

81 Tl

204.

4T

halli

um

107

Bh

[264

.1]

Boh

rium

108

Hs

[277

]H

assi

um

109

Mt

[268

]M

eitn

eriu

m

110

Ds

[271

]D

arm

stad

tium

111

Rg

[272

]R

oent

geni

um

87 Fr[2

23.0

]Fr

anci

um

88 Ra

[226

.0]

Rad

ium

89–1

03

Act

inid

es

104

Rf

[261

.1]

Rut

herf

ordi

um

105

Db

[262

.1]

Dub

nium

106

Sg[2

66.1

]Se

abor

gium

57 La

138.

9L

anth

anum

89 Ac

[227

.0]

Act

iniu

m

1 H1.

008

Hyd

roge

n

Sym

bol o

f el

emen

t

Nam

e of

ele

men

t

PE

RIO

DIC

TA

BL

E O

F T

HE

EL

EM

EN

TS

KE

Y

2 He

4.00

3H

eliu

m

3 Li

6.94

1L

ithiu

m

4 Be

9.01

2B

eryl

lium

Ato

mic

Num

ber

Ato

mic

Wei

ght

79 Au

197.

0G

old

6 C12

.01

Car

bon

8 O16

.00

Oxy

gen

10 Ne

20.1

8N

eon

11 Na

22.9

9So

dium

12 Mg

24.3

1M

agne

sium

14 Si28

.09

Silic

on

16 S32

.07

Sulf

ur

18 Ar

39.9

5A

rgon

19 K39

.10

Pota

ssiu

m

20 Ca

40.0

8C

alci

um

21 Sc44

.96

Scan

dium

22 Ti

47.8

7T

itani

um

23 V50

.94

Van

adiu

m

24 Cr

52.0

0C

hrom

ium

25 Mn

54.9

4M

anga

nese

26 Fe55

.85

Iron

27 Co

58.9

3C

obal

t

28 Ni

58.6

9N

icke

l

29 Cu

63.5

5C

oppe

r

30 Zn

65.4

1Z

inc

32 Ge

72.6

4G

erm

aniu

m

34 Se78

.96

Sele

nium

36 Kr

83.8

0K

rypt

on

37 Rb

85.4

7R

ubid

ium

38 Sr87

.62

Stro

ntiu

m

39 Y88

.91

Yttr

ium

40 Zr

91.2

2Z

irco

nium

41 Nb

92.9

1N

iobi

um

42 Mo

95.9

4M

olyb

denu

m

43 Tc

[97.

91]

Tech

netiu

m

44 Ru

101.

1R

uthe

nium

45 Rh

102.

9R

hodi

um

46 Pd10

6.4

Palla

dium

47 Ag

107.

9Si

lver

48 Cd

112.

4C

adm

ium

50 Sn11

8.7

Tin

52 Te12

7.6

Tellu

rium

54 Xe

131.

3X

enon

55 Cs

132.

9C

aesi

um

56 Ba

137.

3B

ariu

m

57–7

1

Lan

than

ides

72 Hf

178.

5H

afni

um

73 Ta18

0.9

Tant

alum

74 W18

3.8

Tun

gste

n

75 Re

186.

2R

heni

um

76 Os

190.

2O

smiu

m

77 Ir19

2.2

Irid

ium

78 Pt19

5.1

Plat

inum

79 Au

197.

0G

old

80 Hg

200.

6M

ercu

ry

82 Pb20

7.2

Lea

d

84 Po[2

09.0

]Po

loni

um

86 Rn

[222

.0]

Rad

on

58 Ce

140.

1C

eriu

m

59 Pr14

0.9

Pras

eody

miu

m

60 Nd

144.

2N

eody

miu

m

61 Pm[1

44.9

]Pr

omet

hium

62 Sm 150.

4Sa

mar

ium

63 Eu

152.

0E

urop

ium

64 Gd

157.

3G

adol

iniu

m

65 Tb

158.

9Te

rbiu

m

66 Dy

162.

5D

yspr

osiu

m

67 Ho

164.

9H

olm

ium

68 Er

167.

3E

rbiu

m

69 Tm

168.

9T

huliu

m

70 Yb

173.

0Y

tterb

ium

71 Lu

175.

0L

utet

ium

90 Th

232.

0T

hori

um

91 Pa23

1.0

Prot

actin

ium

92 U23

8.0

Ura

nium

93 Np

[237

.0]

Nep

tuni

um

94 Pu[2

44.1

]Pl

uton

ium

95 Am

[243

.1]

Am

eric

ium

96 Cm

[247

.1]

Cur

ium

97 Bk

[247

.1]

Ber

keliu

m

98 Cf

[251

.1]

Cal

ifor

nium

99 Es

[252

.1]

Ein

stei

nium

100

Fm[2

57.1

]Fe

rmiu

m

101

Md

[258

.1]

Men

dele

vium

102

No

[259

.1]

Nob

eliu

m

103

Lr

[262

.1]

Law

renc

ium

Act

inid

es

Lan

than

ides

Whe

re th

e at

omic

wei

ght i

s no

t kno

wn,

the

rela

tive

atom

ic m

ass

of th

e m

ost c

omm

on r

adio

activ

e is

otop

e is

sho

wn

in b

rack

ets.

The

ato

mic

wei

ghts

of

Np

and

Tc

are

give

n fo

r th

e is

otop

es 23

7 Np

and

99T

c.








• Write your Centre Number andStudent Number at the top ofpages 13, 17, 21 and 25

Total marks – 100

Pages 2–27

75 marks


Part A – 15 marks



Part B – 60 marks



Pages 29–38

25 marks



Section II

Section I

Chemistry

115



– 2 –

Section I75 marks




Sample: 2 + 4 = (A) 2 (B) 6 (C) 8 (D) 9

A B C D


A B C D


correct

A B C D

1 Ethanol can be reacted with ethanoic acid to produce ethyl ethanoate. What type ofreaction is this?

(A) Esterification

(B) Hydration

(C) Polymerisation

(D) Reduction

2 Why is research into synthetic biopolymers attracting great interest?

(A) They decompose more easily than traditional synthetic polymers.

(B) They can be produced more cheaply than traditional synthetic polymers.

(C) They have superior physical properties compared to traditional synthetic polymers.

(D) They have superior chemical properties compared to traditional synthetic polymers.

3 Which of the following cations can be identified using a flame test?

(A) Al3+

(B) Cu2+

(C) Mg2+

(D) Zn2+

4 Which term describes the relationship between the compounds shown below?

(A) Allotropes

(B) Isomers

(C) Isotopes

(D) Monomers

H

Br

H

C C H H C C H

Br

H

Br

Br

H

H

– 3 –

5 Which statement best represents Davy’s definition of an acid?

(A) Acids contain oxygen.

(B) Acids are proton donors.

(C) Acids contain replaceable hydrogen.

(D) Acids ionise in solution to form hydrogen ions.

6 Which of the following is the Lewis electron dot formula for ozone?

7 The figure shows the pH values of some substances.

Based on the pH values shown in the figure, which of the following statements about theconcentration of hydrogen ions is correct?

(A) It is twice as great in milk as that in lemon juice.

(B) It is 1 000 000 times greater in soap than in wine.

(C) It is three times greater in wine than in bleach solution.

(D) It is 1 000 times greater in distilled water than in soap.

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14

Stomachacid Wine Milk Seawater Soap Bleach

Lemonjuice

Rainwater

Distilledwater

Bakingsoda

solutionLaundrydetergent

Ovencleaner

(A)

(B)

(C)

(D)

– 4 –

8 Which of the following graphs illustrates the layered structure of the atmosphere?

Alti

tude

(km

)

Temperature (°C)

Troposphere

Mesosphere

Stratosphere

Thermosphere

140

120

100

80

60

40

20

–200 –100 0 100 200 300

(A)

140

120

100

80

60

40

20

–200 –100 0 100 200 300

Alti

tude

(km

)

Thermosphere

Stratosphere

Mesosphere

Troposphere

(B)

Temperature (°C)

Temperature (°C)

140

120

100

80

60

40

20

–200 –100 0 100 200 300

Alti

tude

(km

)

Troposphere

Stratosphere

Mesosphere

Thermosphere

(C)

Thermosphere

Mesosphere

Stratosphere

Troposphere

Temperature (°C)

140

120

100

80

60

40

20

–200 –100 0 100 200 300

Alti

tude

(km

)

(D)

– 5 –

Roland Smith, 2000, Conquering Chemistry, 3rd edition (C) McGraw - Hill Australia Pty Ltd.

9 Ozone reacts with nitric oxide according to the equation

NO(g) + O3(g) → NO2(g) + O2(g)

0.66 g NO(g) was mixed with 0.72 g O3(g).

What is the maximum volume of NO2(g) produced at 0°C and 100 kPa?

(A) 0.34 L

(B) 0.37 L

(C) 0.45 L

(D) 0.50 L

10 Phosgene is prepared from the reaction of carbon monoxide and chlorine in the presenceof a catalyst:

CO(g) + Cl2(g) COCl2(g) ∆H = − 9.93 kJ mol−1

Which of the following sets of conditions would produce the highest yield of phosgene?

(A) High temperature, high pressure

(B) Low temperature, low pressure

(C) Low temperature, high pressure

(D) High temperature, low pressure

– 6 –

11 In gas chromatography, compounds may be separated based on their molecular weight.The smaller the molecular weight the more quickly the compound is detected. A gaschromatographic analysis was performed on a mixture of 1-hexanol, 1-octanol,1-heptanol and 1-pentanol. The results are shown in the diagram.

Which substance does peak X correspond to?

(A) 1-hexanol

(B) 1-octanol

(C) 1-heptanol

(D) 1-pentanol

12 Two of the compounds shown below react together to form a new compound with acoordinate covalent bond.

Which of the following compounds react this way?

(A) Methane and ammonia

(B) Methane and water

(C) Hydrogen fluoride and ammonia

(D) Hydrogen fluoride and methane

H

H

H

C

H H FHN

HH H

OH

Time

Res

pons

e of

det

ecto

rX

– 7 –

13 A student used the apparatus below to determine the molar heat of combustion ofpropanol.

The following results were obtained:

The molar heat of combustion of 1-propanol is 2021 kJ mol−1. Assuming no heat loss,what would be the final temperature of the water?

(A) 24.2°C

(B) 29.1°C

(C) 45.2°C

(D) 48.4°C

Mass of 1-propanol burnt = 0.60 g

Mass of water heated = 200 g

Initial temperature of water = 21.0°C

Thermometer

Can containing 200 g water

Burner containing 1-propanol

– 8 –

14 Four metals Pb, x, y and z, were connected in pairs and the voltage was recorded.

The results obtained are set out in the table below.

What is the order of increasing ease of oxidation of the metals?

(A) z, y, Pb, x

(B) Pb, x, y, z

(C) x, y, Pb, z

(D) x, Pb, y, z

Voltage (V)

0.35

1.10

2.60

Positive terminal

x

Pb

Pb

Negative terminal

Pb

y

z

Metal electrodeMetal electrode

V

Salt bridge

– 9 –

15 Diagram A shows a dry cell. Diagram B shows a lead-acid cell.

Which of the following shows the correctly labelled parts?

LABELS

1 2 3

anode

anode

cathode

cathode

cathode

cathode

anode

anode

negative terminal

positive terminal

negative terminal

positive terminal

(A)

(B)

(C)

(D)

1

2

Electrolyte

Lead dioxideon lead plate

Lead plate

3

3

Diagram A Diagram B

Carbon

– 10 –


BLANK PAGE

– 11 –

BLANK PAGE


– 12 –


Chemistry






(a) Outline the procedure you would use to prepare a standard solution of sodiumhydrogen carbonate from solid sodium hydrogen carbonate.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

(b) Calculate the mass of solid sodium hydrogen carbonate required to make250 mL of 0.12 mol L−1 solution.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

2

3

– 13 –116

Centre Number

Student Number


The structures of two commercially significant monomers are shown.

(a) Identify the common name of ONE of the monomers.

...............................................................................................................................

(b) The uses of polymers are dependent on their properties.

Discuss this statement with reference to a polymer made from one of the abovemonomers.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

(c) Draw the structure of a polymer made from one of the above monomers. 1

3

1

H2C CHH2C CH

Cl

– 14 –

Marks


Analyse the relationship between the position of elements in the Periodic Table, andthe acid–base behaviour of their oxides.

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

Please turn over

4

– 15 –

Marks


The following experiment was performed to investigate the relative activity of metals.The beaker initially contained 250.0 mL of 0.050 mol L−1 copper sulfate solution.

After several hours the dark blue colour of the solution had become lighter and ared-brown deposit had formed on the piece of zinc metal.

(a) Account for the changes observed. Provide a balanced oxidation–reductionequation in your answer.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

The red-brown deposit was removed from the piece of zinc metal and dried. It wasfound to weigh 0.325 g.

(b) Calculate the concentration of copper sulfate solution remaining in the beaker.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

3

3

Copper sulfate solution

Zinc

– 16 –

Marks



Chemistry



A schematic figure of an atomic absorption spectrophotometer is shown.

(a) What is the purpose of the light source and the flame in the figure?

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................


2

Lightsource

Flame(with sample

in it)

Lens

Detector

Prism(or monochromator)

– 17 –117

Centre Number

Student Number



Soil from an industrial site was suspected of being contaminated with mercury.A single sample of the soil was extracted using an approved method. Theresulting solution was analysed five times by atomic absorption spectroscopy(AAS). The results are shown in the table.

The concentration of mercury in the soil sample was calculated using an averageabsorbance of 0.85.

(b) Assess the validity and reliability of the concentration of mercury determinedusing this procedure.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

End of Question 20

4

Absorbance at259 nm

0.90

0.89

0.89

0.64

0.91

Measurementnumber

1

2

3

4

5

– 18 –

Marks


You have performed first-hand investigations on water samples using qualitative andquantitative analyses.

(a) Distinguish between qualitative analysis and quantitative analysis.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

(b) Describe TWO factors that affect the concentrations of ions in natural bodies ofwater.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

(c) Complete the following table to show how the anions listed can be identified.

Observations if anion is presentReagentAnion

Cl−

PO43−

SO42−

3

2

2

– 19 –

Marks


(a) Define the term amphiprotic.

...............................................................................................................................

...............................................................................................................................

(b) Write TWO chemical equations to show that the dihydrogen phosphate ion(H2PO4

−) is amphiprotic.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

2

1

– 20 –

Marks



Chemistry



A natural indicator was made by heating yellow flowers with water. The resultingyellow solution was tested with a range of substances. The results are recorded below.

Assess the usefulness of the yellow solution as an acid–base indicator.

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

Colour

Red

Yellow

Orange

Yellow

Yellow

Substance

0.1 M hydrochloric acid

0.1 M ammonia

Lemon juice

Oven cleaner

Pure water

3

– 21 –118

Centre Number

Student Number


The diagram shows three reagent bottles containing acids.

(a) Calculate the pH after 10.0 mL of 0.01 mol L−1 hydrochloric acid solution isdiluted by the addition of 90.0 mL of distilled water.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

(b) Explain the use of acetic acid and citric acid as food additives.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................


2

1

0.01 mol L−1

Acetic acid0.01 mol L−1

Citric acid0.01 mol L−1

Hydrochloric acid

pH = 3.38 pH = 2.56 pH = 2.00

– 22 –

Marks


(c) Explain the difference in pH between the three acids in the diagram.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

End of Question 24

Please turn over

2

– 23 –

Marks


The table shows properties of some fuels.

Assess the potential of ethanol as an alternative fuel, making use of data from thetable.

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

Boiling point (°C)

–161.5

–42.1

125.7

78.3

Heat of combustion (kJ g–1)

55.6

50.3

47.9

29.7

Main sources

• Petrochemical industry

• Petrochemical industry• Natural gas

• Refined from crude oil

• Hydration of ethene• Fermentation

Fuel

Methane

Propane

Octane

Ethanol

5

– 24 –

Marks



Chemistry



Discuss the benefits and problems associated with the use of ONE radioactive isotopein industry.

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

4

– 25 –119

Centre Number

Student Number


The table shows ozone depletion potential (ODP) for different compounds.

Ozone depletion potential

Discuss the problems associated with the use of CFCs, and assess the suitability ofalternative chemicals as replacements, using data in the table.

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................


1.0 CFC 111.0CFC 12

1.0CFC 114

HCFC 22HCFC 123

HCFC 141bHCFC 142b

HFC 32HFC 125

HFC 134aHFC 143a

0.8CFC 113

0.0550.02

0.110.065

0000

7

– 26 –

Marks

http://www.princeton.edu/nchm333/2002/spring/ozone/alternatives_substitutes.htm


.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

End of Question 27

– 27 –

BLANK PAGE


– 28 –


Chemistry

Section II




Pages




Question 31 The Chemistry of Art ................................................................. 36


– 29 –120


(a) (i) Identify a safety precaution used when diluting concentrated sulfuric acid.

(ii) Many of the steps in the Contact process for the manufacture of sulfuricacid are reversible equilibrium reactions. Identify ONE of thesereactions and describe how the product yield can be maximised.

(b) The table shows the structures of three different classes of detergents.

(i) Account for the cleaning action of anionic detergents.

(ii) Assess the environmental impacts of the different classes of detergents.


4

2

N+

StructureType of

detergent

Anionic

Non-ionic

Cationic

OH

SO3

3

1

– 30 –

Marks



(c) Chemco Pty Ltd wishes to build two new industrial plants. One will be used forthe production of sodium carbonate and the other for production of sodiumhydroxide. The map shows three sites, labelled A, B and C, being considered forthe location of the industrial plants.

Assess the suitability of the three sites for locating industrial plants to produceeach compound.

(d) During your practical work you performed a first-hand investigation to gatherinformation and describe the properties of a named emulsion, and you relatedthese properties to its uses.

(i) Define the term emulsion.

(ii) Outline the procedure used in your investigation, and describe the resultsobtained.

(iii) Explain how the industrial method of producing soap differs from thatused in school laboratories.

End of Question 28

4

3

1

Powerstation

Smalltown

Smalltown

Largecity

Port

Port

Limestonedeposits

River

Coast

KEY

Railway line

7

– 31 –

Marks


(a) (i) Identify ONE origin of minerals in oceans.

(ii) Explain the damage that occurs when drying wooden artefacts that havebeen removed from long-submerged wrecks.

(b) The diagram shows an electrolytic cell.

(i) Write half-equations for the main reactions occurring at the cathode andanode.

(ii) Analyse the impact of the work of Faraday on our understanding ofelectrolysis.

(c) Assess how increasing knowledge of metals and alloys has resulted in materialsother than timber being used to construct ships.


7

4

2

Platinumelectrode

Solutionof KBr

Platinumelectrode

3

1

– 32 –

Marks


(d) During your practical work you performed a first-hand investigation to compareand describe the rates of corrosion of materials at different oxygen concentrations.

(i) Define the term corrosion.


(iii) The diagram shows the locations of two identical steel ships that werewrecked at the same time near a tropical island.

Explain how differences in oxygen concentration and temperatureexperienced by the two wrecks have resulted in different levels ofcorrosion.

End of Question 29

30 m

4

3

1

– 33 –

Marks


(a) (i) Identify the following molecule:

(ii) Compare the formation of this molecule by anaerobic respiration withthe process of fermentation.

(b) The diagram illustrates schematically the current model of muscle contraction.

(i) Identify protein A, protein B, and metal ion C.

(ii) Explain why different energy sources are used in sprinting and lightexercise.


4

2

Protein BProtein A

Metalion

ATP

ADP + Pi

C

3

H

H

H

C C C

OH O

OHH

1

– 34 –

Marks


(c) Assess the importance of oxidative phosphorylation as an energy source,referring to the roles of cytochromes and oxygen.

(d) During your practical work you performed a first-hand investigation on theeffect of pH on the reaction of an enzyme.

(i) Define the term enzyme.


(iii) Explain the possible effects of varying pH on the primary, secondary andtertiary structures of enzymes.

End of Question 30

4

3

1

7

– 35 –

Marks


(a) The formulae of three coordination complexes containing chromium(III) areshown below.

(i) What is the electron configuration of chromium metal in the ground state?

(ii) Draw a Lewis structure of ONE of these coordination complexes, andexplain the bonding in this molecule.

(b) The diagram shows the emission spectrum of sodium seen through a spectroscope.

(i) Draw an energy level diagram to represent the origin of these spectrallines.

(ii) Explain how the Bohr model of the atom was developed using theemission spectrum of hydrogen, and outline its limitations.

(c) Assess the potential health risks associated with chemicals found in cosmeticsthat were used in an ancient culture.

(d) During your practical work you performed a first-hand investigation to observethe colour changes of a named transition element as it changed in oxidation state.

(i) Define the term transition element.


(iii) Explain why transition elements may have more than one oxidation state. 4

3

1

7

4

2

400 nm500600700

3

1

Cr H O

Cr H O Cl

Cr H O Cl

2

2

2 2

( )[ ]( )[ ]( )[ ]

+

+

+

6

3

5

2

4

– 36 –

Marks


(a) (i) Identify the technique used to separate amino acids on the basis ofdifferences in their charge.

(ii) Explain how a mass spectrometer operates, and identify its usefulness forforensic science.

(b) Oxytocin and vasopressin are small proteins consisting of nine amino acids. Aforensic scientist decided to determine the amino acid composition of bothproteins using paper chromatography. Samples of both proteins were firsthydrolysed into their constituent amino acids using a mixture of enzymes. Theresulting protein hydrolysates were spotted onto a sheet of filter paper togetherwith eleven reference amino acids. After the filter paper had been placed in asuitable solvent and developed, the chromatogram below was obtained.

(i) Contrast the amino acid composition of both proteins after analysing thechromatogram.

(ii) Explain how variations in the composition and structure of proteinsaffect their biological functions.


4

2

Solventfront

Start point

Solventflow

Ty As Ph Va Gly Le Glu Hi Ar Il Pr S1 S2

KEY

Ty = TyrosineAs = AsparaginePh = PhenylalanineVa = ValineGly = GlycineLe = LeucineGlu = Glutamic acidHi = HistidineAr = ArginineIl = IsoleucinePr = Proline

S1 = Vasopressinhydrolysate

S2 = Oxytocinhydrolysate

3

1

– 37 –

Marks


(c) Assess the usefulness of distinguishing tests for carbohydrates and metal ionsused in the school laboratory, compared with technology used by forensicchemists in laboratories, for the same purposes.

(d) During your practical work you performed a first-hand investigation to identifythe range of solvents that may be used for chromatography to separate andidentify mixtures.

(i) Define the term chromatography.


(iii) Describe precautions used to prevent contamination of forensic samples,and explain why they are needed.

End of paper

4

3

1

7

– 38 –

Marks

BLANK PAGE

– 39 –

BLANK PAGE


– 40 –

– 41 –

DATA SHEET








Chemistry


K+ + e– K(s) –2.94 V

Ba2+ + 2e– Ba(s) –2.91 V

Ca2+ + 2e– Ca(s) –2.87 V

Na+ + e– Na(s) –2.71 V

Mg2+ + 2e– Mg(s) –2.36 V

Al3+ + 3e– Al(s) –1.68 V

Mn2+ + 2e– Mn(s) –1.18 V

H2O + e– 1–2 H2(g) + OH– –0.83 V

Zn2+ + 2e– Zn(s) –0.76 V

Fe2+ + 2e– Fe(s) –0.44 V

Ni2+ + 2e– Ni(s) –0.24 V

Sn2+ + 2e– Sn(s) –0.14 V

Pb2+ + 2e– Pb(s) –0.13 V

H+ + e– 1–2 H2(g) 0.00 V

SO42– + 4H+ + 2e– SO2(aq) + 2H2O 0.16 V

Cu2+ + 2e– Cu(s) 0.34 V

1–2 O2(g) + H2O + 2e– 2OH– 0.40 V

Cu+ + e– Cu(s) 0.52 V

1–2 I2(s) + e– I– 0.54 V

1–2 I2(aq) + e– I– 0.62 V

Fe3+ + e– Fe2+ 0.77 V

Ag+ + e– Ag(s) 0.80 V

1–2 Br2(l) + e– Br– 1.08 V

1–2 Br2(aq) + e– Br– 1.10 V

1–2 O2(g) + 2H+ + 2e– H2O 1.23 V

1–2 Cl2(g) + e– Cl– 1.36 V

1–2 Cr2O72– + 7H+ + 3e– Cr3+ + 7–2 H2O 1.36 V

1–2 Cl2(aq) + e– Cl– 1.40 V

MnO4– + 8H+ + 5e– Mn2+ + 4H2O 1.51 V

1–2 F2(g) + e– F– 2.89 V

– 42 –

1179 F

19.0

0Fl

uori

ne

17 Cl

35.4

5C

hlor

ine

35 Br

79.9

0B

rom

ine

53 I12

6.9

Iodi

ne

85 At

[210

.0]

Ast

atin

e

1157 N

14.0

1N

itrog

en

15 P30

.97

Phos

phor

us

33 As

74.9

2A

rsen

ic

51 Sb12

1.8

Ant

imon

y

83 Bi

209.

0B

ism

uth

1135 B

10.8

1B

oron

13 Al

26.9

8A

lum

iniu

m

31 Ga

69.7

2G

alliu

m

49 In11

4.8

Indi

um

81 Tl

204.

4T

halli

um

107

Bh

[264

.1]

Boh

rium

108

Hs

[265

.1]

Has

sium

109

Mt

[268

]M

eitn

eriu

m

110

Uun —

Unu

nnili

um

111

Uuu —

Unu

nuni

um

112

Uub —

Unu

nbiu

m

114

Uuq —

Unu

nqua

dium

116

Uuh —

Unu

nhex

ium

118

Uuo —

Unu

noct

ium

87 Fr[2

23.0

]Fr

anci

um

88 Ra

[226

.0]

Rad

ium

89–1

03

Act

inid

es

104

Rf

[261

.1]

Rut

herf

ordi

um

105

Db

[262

.1]

Dub

nium

106

Sg[2

63.1

]Se

abor

gium

57 La

138.

9L

anth

anum

89 Ac

[227

.0]

Act

iniu

m

1 H1.

008

Hyd

roge

n

Sym

bol o

f el

emen

t

Nam

e of

ele

men

t

PE

RIO

DIC

TA

BL

E O

F T

HE

EL

EM

EN

TS

KE

Y

2 He

4.00

3H

eliu

m

3 Li

6.94

1L

ithiu

m

4 Be

9.01

2B

eryl

lium

Ato

mic

Num

ber

Ato

mic

Wei

ght

79 Au

197.

0G

old

6 C12

.01

Car

bon

8 O16

.00

Oxy

gen

10 Ne

20.1

8N

eon

11 Na

22.9

9So

dium

12 Mg

24.3

1M

agne

sium

14 Si28

.09

Silic

on

16 S32

.07

Sulf

ur

18 Ar

39.9

5A

rgon

19 K39

.10

Pota

ssiu

m

20 Ca

40.0

8C

alci

um

21 Sc44

.96

Scan

dium

22 Ti

47.8

7T

itani

um

23 V50

.94

Van

adiu

m

24 Cr

52.0

0C

hrom

ium

25 Mn

54.9

4M

anga

nese

26 Fe55

.85

Iron

27 Co

58.9

3C

obal

t

28 Ni

58.6

9N

icke

l

29 Cu

63.5

5C

oppe

r

30 Zn

65.3

9Z

inc

32 Ge

72.6

1G

erm

aniu

m

34 Se78

.96

Sele

nium

36 Kr

83.8

0K

rypt

on

37 Rb

85.4

7R

ubid

ium

38 Sr87

.62

Stro

ntiu

m

39 Y88

.91

Yttr

ium

40 Zr

91.2

2Z

irco

nium

41 Nb

92.9

1N

iobi

um

42 Mo

95.9

4M

olyb

denu

m

43 Tc

[98.

91]

Tech

netiu

m

44 Ru

101.

1R

uthe

nium

45 Rh

102.

9R

hodi

um

46 Pd10

6.4

Palla

dium

47 Ag

107.

9Si

lver

48 Cd

112.

4C

adm

ium

50 Sn11

8.7

Tin

52 Te12

7.6

Tellu

rium

54 Xe

131.

3X

enon

55 Cs

132.

9C

aesi

um

56 Ba

137.

3B

ariu

m

57–7

1

Lan

than

ides

72 Hf

178.

5H

afni

um

73 Ta18

0.9

Tant

alum

74 W18

3.8

Tun

gste

n

75 Re

186.

2R

heni

um

76 Os

190.

2O

smiu

m

77 Ir19

2.2

Irid

ium

78 Pt19

5.1

Plat

inum

79 Au

197.

0G

old

80 Hg

200.

6M

ercu

ry

82 Pb20

7.2

Lea

d

84 Po[2

10.0

]Po

loni

um

86 Rn

[222

.0]

Rad

on

58 Ce

140.

1C

eriu

m

59 Pr14

0.9

Pras

eody

miu

m

60 Nd

144.

2N

eody

miu

m

61 Pm[1

46.9

]Pr

omet

hium

62 Sm 150.

4Sa

mar

ium

63 Eu

152.

0E

urop

ium

64 Gd

157.

3G

adol

iniu

m

65 Tb

158.

9Te

rbiu

m

66 Dy

162.

5D

yspr

osiu

m

67 Ho

164.

9H

olm

ium

68 Er

167.

3E

rbiu

m

69 Tm

168.

9T

huliu

m

70 Yb

173.

0Y

tterb

ium

71 Lu

175.

0L

utet

ium

90 Th

232.

0T

hori

um

91 Pa23

1.0

Prot

actin

ium

92 U23

8.0

Ura

nium

93 Np

[237

.0]

Nep

tuni

um

94 Pu[2

39.1

]Pl

uton

ium

95 Am

[241

.1]

Am

eric

ium

96 Cm

[244

.1]

Cur

ium

97 Bk

[249

.1]

Ber

keliu

m

98 Cf

[252

.1]

Cal

ifor

nium

99 Es

[252

.1]

Ein

stei

nium

100

Fm[2

57.1

]Fe

rmiu

m

101

Md

[258

.1]

Men

dele

vium

102

No

[259

.1]

Nob

eliu

m

103

Lr

[262

.1]

Law

renc

ium

Act

inid

es

Lan

than

ides

Whe

re th

e at

omic

wei

ght i

s no

t kno

wn,

the

rela

tive

atom

ic m

ass

of th

e m

ost c

omm

on r

adio

activ

e is

otop

e is

sho

wn

in b

rack

ets.

The

ato

mic

wei

ghts

of

Np

and

Tc

are

give

n fo

r th

e is

otop

es 23

7 Np

and

99T

c.








• Write your Centre Number andStudent Number at the top ofpages 13, 17, 21 and 25

Total marks – 100

Pages 2–28

75 marks


Part A – 15 marks



Part B – 60 marks



Pages 29–37

25 marks



Section II

Section I

Chemistry

115



– 2 –

Section I75 marks




Sample: 2 + 4 = (A) 2 (B) 6 (C) 8 (D) 9

A B C D


A B C D


correct

A B C D

1 Which of the following is an acid–base indicator?

(A) Methanol

(B) Methyl orange

(C) Methanoic acid

(D) Methyl ethanoate

2 Which of the following is a transuranic element?

(A) Caesium

(B) Cerium

(C) Chromium

(D) Curium

3 Which instrument is used to detect radiation from radioactive isotopes?

(A) pH meter

(B) Geiger counter

(C) Ion-selective electrode

(D) Atomic absorption spectrophotometer (AAS)

4 In which layer of the atmosphere does ozone act as a UV radiation shield?

(A) Mesosphere

(B) Stratosphere

(C) Thermosphere

(D) Troposphere

– 3 –

5 Which of the following could be used to determine the total dissolved solids in a sampleof muddy river water?

(A) P and Q

(B) R and S

(C) P and R

(D) Q and S

6 The table gives the heat of combustion in kJ g−1 for a number of different fuels.

The heat of combustion in kJ mol−1 for one of the fuels was calculated as 2016 kJ mol−1.What was the fuel?

(A) Methanol

(B) Ethanol

(C) Propanol

(D) Petrol

Heat of combustion(kJ g−1)

22.7

29.6

33.6

47.8

Fuel

Methanol

Ethanol

Propanol

Petrol (octane)

QP R S

– 4 –

7 The diagram is a representation of the Periodic Table. The positions of six differentelements are shown.

What are the reactions of oxides of these elements with acid and with base?

8 A sulfuric acid solution has a concentration of 5 × 10−4 mol L−1.

What is the pH of this solution, assuming the acid is completely ionised?

(A) 3.0

(B) 3.3

(C) 3.6

(D) 4.0

9 What is the name of the compound shown?

(A) 1-chloro-1,2-difluoropropane

(B) 3-chloro-2,3-difluoropropane

(C) 1,2-difluoro-1-chloropropane

(D) 1-chloro-1,2-difluoropentane

—

F

H—C—C—C—H

—

H

—

H

—

H

—

F

—

Cl

Oxide reacts with acid and with base

V

U

V

Y

Oxide reacts with base

X

X

Z

W

Oxide reacts with acid

Z

Y

X

V

(A)

(B)

(C)

(D)

YV Z

W

U

X

– 5 –

10 The graph shows October ozone concentrations above Halley Bay in Antarctica between1956 and 1998.

Based on these data alone, which of the following is a valid statement about theconcentration of ozone above Halley Bay?

(A) It was greater in 1998 than in 1993.

(B) It will be greater in 2004 than in 1998.

(C) The variation in ozone concentration between 1960 and 1970 was due to changesin atmospheric CFC concentrations.

(D) The variation in ozone concentration from one year to the next is due only tochanges in atmospheric CFC concentrations.

1950

100

150

200

250

300

350

1960 1970 1980 1990 2000Year

October ozoneconcentrations

– 6 –

11 Which polymer is made by the polymerisation of methyl methacrylate?

methyl methacrylate

(A) —CH2—C=C—CH2—C=C—CH2—C=C—

—CH3

—

CH3

—

CH3—

OCH3

—

OCH3

—

OCH3

(B) —CH2—C—CH2—C—CH2—C—

—

CH3

—

CH3—

CH3

—

COOCH3

—

COOCH3

—

COOCH3

(C) HC—CH3 HC—CH3 HC—CH3

—

—CH—

—

CH—

—

CH—

—

COOCH3

—

COOCH3

—

COOCH3

(D) —C—C—C—

——

COOCH3

CH3

——

COOCH3

CH3

——

COOCH3

CH3

H2C=C—COOCH3

—

CH3

– 7 –

12 The graph shows the mass and amount of carbon, fluorine and chlorine atoms in onemole of a compound.

What is the molecular formula for this compound?

(A) CF2Cl

(B) CF2Cl2

(C) C2F3Cl3

(D) C2F4Cl2

0

5

10

15

20

25

0

20

40

60

80

100

Carbon Fluorine Chlorine

Mass(g)

Amount(mol)

Mass (g) Amount (mol)

– 8 –

13 A student performed three tests to investigate the relative activity of metals. In each testa metal strip was placed in a solution containing ions of a different metal. The results areshown in the diagrams.

What is the order of activity of the metals, based on these results?

(A) X > Z > Y

(B) Y > X > Z

(C) Z > Y > X

(D) Z > X > Y

14 In a titration of a strong base with a strong acid, the following procedure was used:

1. A burette was rinsed with water and then filled with the standard acid.

2. A pipette was rinsed with some base solution.

3. A conical flask was rinsed with some base solution.

4. A pipette was used to transfer a measured volume of base solution into the conical flask.

5. Indicator was added to the base sample and it was titrated to the endpoint with the acid.

Which statement is correct?

(A) The calculated base concentration will be correct.

(B) The calculated base concentration will be too low.

(C) The calculated base concentration will be too high.

(D) No definite conclusion can be reached about the base concentration.

Metal X

Y2+

Metal Ydeposited on X

Metal Z

Y2+

Metal Ydeposited on Z

Metal X

Z2+

No reaction

– 9 –

15 Which of the following graphs shows how pH will vary when dilute HCl is added to100 mL of dilute natural buffer solution with an initial pH of 7.0?

pH

2

0

4

6

8

10

12

14

0 40 60 8020

Volume of HCl added (mL)

pH

2

0

4

6

8

10

12

14

0 40 60 8020


pH

2

0

4

6

8

10

12

14

0 40 60 8020


2

0

4

6

8

10

12

14

0 40 60 8020


pH

(A) (B)

(C) (D)

– 10 –

BLANK PAGE

– 11 –

BLANK PAGE


– 12 –






You performed a first-hand investigation that monitored mass changes during thefermentation of glucose to ethanol.

(a) Outline the procedure you used.

....................................................................................................................................

....................................................................................................................................

....................................................................................................................................

....................................................................................................................................

....................................................................................................................................

....................................................................................................................................

....................................................................................................................................

....................................................................................................................................

....................................................................................................................................

(b) Write a balanced chemical equation for this reaction.

....................................................................................................................................

....................................................................................................................................

1

2


Chemistry

– 13 –116

Centre Number

Student Number


The flowchart shows the production of polyethylene.

(a) Identify Compound X.

...............................................................................................................................

(b) Describe Process Y.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................


3

1

Compound X

Ethylene

Polyethylene

Dehydration

Process Y

– 14 –

Marks


A sample of polyethylene was produced by Process Y. The following graph shows thedistribution of molecular weights of polymer molecules in the sample.

(c) Why is a range of molecular weights observed?

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

End of Question 17

Please turn over

1

Molecular weight

Number ofpolymer

molecules

– 15 –

Marks


Describe how commercial radioisotopes are produced, and how transuranic elementsare produced.

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

4

– 16 –

Marks


Section I — Part B (continued)


(a) Identify the cathode in this diagram.

...............................................................................................................................

(b) Write the net redox equation for the cell reaction, and calculate the cellpotential (E°–).

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

2

1

V

Lead

Salt bridge

Silver

Ag+

(1 mol L−1)Pb2+

(1 mol L−1)


Chemistry

– 17 –117

Centre Number

Student Number


Assess the suitability of biomass as a future source of energy and chemicals for industry.

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

5

– 18 –

Marks


You performed a first-hand investigation to prepare an ester by reflux.

(a) Identify the products formed when propanoic acid and butanol are refluxed withacid catalyst.

...............................................................................................................................

...............................................................................................................................

(b) Draw a fully labelled diagram of the equipment assembled for use.

(c) Outline the advantages of using reflux to prepare the ester.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

2

2

1

– 19 –

Marks


(a) Write a balanced chemical equation for the complete combustion of ethanol.

....................................................................................................................................

....................................................................................................................................

(b) A mass of 72.5 g of ethanol was burnt completely in air. Calculate the volumeof carbon dioxide that was produced at 25°C and 100 kPa.

....................................................................................................................................

....................................................................................................................................

....................................................................................................................................

....................................................................................................................................

....................................................................................................................................

....................................................................................................................................

2

1

– 20 –

Marks




25.0 mL of 0.12 mol L−1 standard barium hydroxide solution was titrated with nitricacid. The results are recorded in the table.

(a) Write a balanced chemical equation for the reaction of barium hydroxide withnitric acid.

...............................................................................................................................

...............................................................................................................................

(b) Calculate the concentration of the nitric acid.

....................................................................................................................................

....................................................................................................................................

....................................................................................................................................

....................................................................................................................................

....................................................................................................................................

....................................................................................................................................

....................................................................................................................................

....................................................................................................................................

3

1

Volume of nitric acid used(mL)

20.4

18.1

18.2

18.1

Titration

1

2

3

4


Chemistry

– 21 –118

Centre Number

Student Number


Discuss factors that must be considered when using neutralisation reactions to safelyminimise damage in chemical spills.

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

4

– 22 –

Marks


Explain the trends in boiling points shown in the graph.

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

60500

100

200

70 80 90 100 110Molecular weight

Boilingpoint (°C)

Alkanoic acids

Alkanols

Alkanes

4

– 23 –

Marks


Describe the process of eutrophication, and assess the suitability of water quality testsused to monitor it.

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

4

– 24 –

Marks




A student carried out an investigation to analyse the sulfate content of lawn fertiliser.The student weighed out 1.0 g of fertiliser and dissolved it in water. 50 mL of0.25 mol L−1 barium chloride solution was then added. A white precipitate of bariumsulfate formed, which weighed 1.8 g.

(a) Calculate the percentage by mass of sulfate in the fertiliser.

....................................................................................................................................

....................................................................................................................................

....................................................................................................................................

....................................................................................................................................

....................................................................................................................................

....................................................................................................................................

(b) Evaluate the reliability of the experimental procedure used.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

3

2


Chemistry

– 25 –119

Centre Number

Student Number


The results of analysis of a set of standard cadmium solutions are presented in the table.

(a) Draw an appropriate graph of the data.


0 2 4 6 8 10 12 14Concentration of cadmium (ppm)

1.00

0.90

0.80

0.70

0.60

0.50

0.40

0.30

0.20

0.10

0

Abs

orba

nce

2

Absorbance

0.00

0.22

0.38

0.62

0.83

Concentration of cadmiumstandard solution

(ppm)

0

3

6

9

12

– 26 –

Marks


The map shows a catchment area. There is an industrial plant, a sewage treatmentplant and a small town, all of which discharge water into the river. Water samples werecollected at four sites.

The results of analysis of cadmium levels from these four sites are given in the table.

(b) Justify your conclusion about the most likely source of cadmium pollution.

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

...............................................................................................................................

End of Question 28

2

Absorbance

0.08

0.15

0.55

0.40

Sample site

Site 1

Site 2

Site 3

Site 4

Site 1

Site 3

Site 4

Site 2Sewage treatment plant

Town

Mountainrange

Industrialplant

Ocean

– 27 –

Marks


Evaluate the importance of monitoring and managing the conditions used in the Haberprocess.

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

.........................................................................................................................................

7

– 28 –

Marks


Section II




Pages

Question 30 Industrial Chemistry ................................................................... 30

Question 31 Shipwrecks, Corrosion and Conservation .................................. 31





Chemistry

– 29 –120


(a) (i) Identify ONE use of sulfuric acid in industry.

(ii) One of the starting materials used for preparing sulfuric acid is sulfur.Describe the process used to extract sulfur from mineral deposits.

(b) During your practical work you performed a first-hand investigation to identifythe products of electrolysis of sodium chloride.

(i) Describe ONE precaution you took to minimise hazards, or to disposeof reactants and products safely.

(ii) Outline the procedure you used to identify the products of electrolysis ofsodium chloride.

(c) Analyse how an understanding of the structure and cleaning action of soaps ledto the development of synthetic detergents.

(d) The Ostwald process is used for making nitric acid from ammonia, and involvesseveral equilibrium steps.

(i) Identify the only factor that changes the value of an equilibrium constant.

(ii) One step in the process produces nitrogen dioxide according to theequation:

2NO(g) + O2(g) 2NO2(g).

This reaction is exothermic. Describe TWO methods that could be usedto increase the yield of nitrogen dioxide.

(iii) A 1 L reaction vessel initially contained 0.25 mol NO and 0.12 mol O2.After equilibrium was established there was only 0.05 mol NO.

Calculate the equilibrium constant for the reaction. Show all relevantworking.

(e) Assess how environmental issues have been addressed in an industrial methodof production of an acid, and an industrial method of production of a base.

6

3

2

1

5

3

1

3

1

– 30 –

Marks


(a) (i) Identify ONE passivating metal.

(ii) Account for the differences in corrosion of active and passivating metals.Include a relevant balanced chemical equation in your answer.

(b) During your practical work you performed a first-hand investigation to identifythe factors that affect the rate of an electrolysis reaction.


(ii) Outline the procedure you used to show how ONE factor affects the rateof an electrolysis reaction.

(c) The Titanic struck an iceberg in 1912 and sank to a depth of more than threekilometres.

Analyse how theories about corrosion at great ocean depth have changed sincethe recent discovery of extensive corrosion on wrecks such as the Titanic.

(d) Fishermen face a problem of limiting corrosion of their steel fish hooks. Afisherman has the choice of storing his steel fish hooks in a plastic, copper oraluminium container.

(i) What is the main metal in steel?

(ii) Compare the effectiveness of these containers in limiting corrosion ofsteel fish hooks.

(e) Assess how an understanding of electrolysis has contributed to the developmentof methods for cleaning and restoring marine artefacts.

6

5

1

5

3

1

3

1

– 31 –

Marks


(a) (i) Identify the role of glycogen in human muscle and liver.

(ii) Describe the process of bond formation when glucose molecules react toform glycogen.

(b) During your practical work you performed a first-hand investigation to comparethe structures of fatty acids and glycerol.

(i) Describe the results of your investigation.

(ii) Outline why glycerol is more soluble in water than are fatty acids that arecommonly found in the body.

(c) Analyse how an understanding of the composition and structure of proteins ledto the current theory of muscle contraction.


5

2

2

3

1

– 32 –

Marks


(d) The flowchart summarises the production of ATP from glucose and stearic acid.

(i) Identify Pathway P.

(ii) Construct a word-equation that summarises the formation of products inPathway P, when one molecule of glucose is metabolised.

(iii) Explain why fats can produce more energy per carbon atom thancarbohydrates.

(e) Evaluate the importance of the chemistry of ATP in metabolic processes.

End of Question 32

6

3

2

1

glucose (6 C-atoms)

acetyl Coenzyme A

pyruvate

Pathway P

TCA Cycle

Oxidative phosphorylation(Cytochrome chain)

stearic acid (18 C-atoms)(a common fatty acid)

146 ATP moleculesper stearic acid molecule

36 ATP moleculesper glucose molecule

Oxidation

– 33 –

Marks


(a) (i) What is the maximum number of electrons found in an atomic orbital?

(ii) The graph shows the first five ionisation energies for sodium, aluminiumand magnesium.

Explain how the data can be used to provide information about thearrangement of electrons around the atoms.

(b) During your practical work you performed a first-hand investigation to observethe flame colour of different metal ions.

(i) Explain the precautions you took during your investigation.

(ii) Outline the procedure you used to observe the flame colour of differentmetal ions.

(c) Analyse the relationship between the chemical composition and properties,including colour, of pigments used in traditional art by Aboriginal people.


5

2

2

00

5 000

10 000

15 000

1st 2nd 3rd 4th 5th 6th

Na

Al

Mg

Electron removed

Ionisationenergy

(kJ mol−1)

3

1

– 34 –

Marks


(d) In the early 1900s, many Australian children were diagnosed as having Pinkdisease.

The symptoms included pain, loss of teeth, and the presence of a pink colour onfingers and toes.

The first indication that Pink disease was due to mercury poisoning came fromthe successful treatment of the children using EDTA.

(i) Identify the block in the Periodic Table in which mercury is present.

(ii) Explain why transition metals such as mercury may have more than oneoxidation state.

(iii) Explain why chelating ligands such as EDTA are often used to treatpoisoning by heavy metals.

(e) Evaluate the usefulness of the range of technologies used by chemists to identifypigments.

End of Question 33

6

3

2

1

C

CH2CH2

O–

C

O–

O

O

NCH2

C

CH2 O–CH2 C

O–

O

O

NCH2

EDTA

– 35 –

Marks


(a) (i) Identify the general class of compounds represented by the formulaCx(H2O)y.

(ii) Describe TWO tests that can be used to distinguish between some of thefollowing classes of organic compounds: alkanes, alkenes, alkanols andalkanoic acids.

(b) During your practical work you performed a first-hand investigation todistinguish between reducing and non-reducing sugars.


(ii) Outline the procedure you used to distinguish between reducing andnon-reducing sugars.

(c) Analyse how emission spectra of elements assist in the identification of theorigins of a mixture.


5

3

1

3

1

– 36 –

Marks


(d) The diagram shows the results of an investigation to identify the parents of achild. The DNA fingerprints from the mother (M) and child (C) are labelled.Also shown are the DNA fingerprints from two possible fathers (F1) and (F2).

(i) Identify the more probable father.

(ii) Outline the structure and composition of DNA.

(iii) Describe how DNA fingerprints are produced, and explain why they canbe used to show that two people belong to the same family.

(e) Evaluate how the development of chromatographic methods has advancedforensic science.

End of paper

6

3

2

1

M C F1 F2

– 37 –

Marks

BLANK PAGE

– 38 –

BLANK PAGE

– 39 –

BLANK PAGE


– 40 –

– 41 –

DATA SHEET








Chemistry


K+ + e– K(s) –2.94 V

Ba2+ + 2e– Ba(s) –2.91 V

Ca2+ + 2e– Ca(s) –2.87 V

Na+ + e– Na(s) –2.71 V

Mg2+ + 2e– Mg(s) –2.36 V

Al3+ + 3e– Al(s) –1.68 V

Mn2+ + 2e– Mn(s) –1.18 V

H2O + e– 1–2 H2(g) + OH– –0.83 V

Zn2+ + 2e– Zn(s) –0.76 V

Fe2+ + 2e– Fe(s) –0.44 V

Ni2+ + 2e– Ni(s) –0.24 V

Sn2+ + 2e– Sn(s) –0.14 V

Pb2+ + 2e– Pb(s) –0.13 V

H+ + e– 1–2 H2(g) 0.00 V

SO42– + 4H+ + 2e– SO2(aq) + 2H2O 0.16 V

Cu2+ + 2e– Cu(s) 0.34 V

1–2 O2(g) + H2O + 2e– 2OH– 0.40 V

Cu+ + e– Cu(s) 0.52 V

1–2 I2(s) + e– I– 0.54 V

1–2 I2(aq) + e– I– 0.62 V

Fe3+ + e– Fe2+ 0.77 V

Ag+ + e– Ag(s) 0.80 V

1–2 Br2(l) + e– Br– 1.08 V

1–2 Br2(aq) + e– Br– 1.10 V

1–2 O2(g) + 2H+ + 2e– H2O 1.23 V

1–2 Cl2(g) + e– Cl– 1.36 V

1–2 Cr2O72– + 7H+ + 3e– Cr3+ + 7–2 H2O 1.36 V

1–2 Cl2(aq) + e– Cl– 1.40 V

MnO4– + 8H+ + 5e– Mn2+ + 4H2O 1.51 V

1–2 F2(g) + e– F– 2.89 V

– 42 –

1179 F

19.0

0Fl

uori

ne

17 Cl

35.4

5C

hlor

ine

35 Br

79.9

0B

rom

ine

53 I12

6.9

Iodi

ne

85 At

[210

.0]

Ast

atin

e

1157 N

14.0

1N

itrog

en

15 P30

.97

Phos

phor

us

33 As

74.9

2A

rsen

ic

51 Sb12

1.8

Ant

imon

y

83 Bi

209.

0B

ism

uth

1135 B

10.8

1B

oron

13 Al

26.9

8A

lum

iniu

m

31 Ga

69.7

2G

alliu

m

49 In11

4.8

Indi

um

81 Tl

204.

4T

halli

um

107

Bh

[264

.1]

Boh

rium

108

Hs

[265

.1]

Has

sium

109

Mt

[268

]M

eitn

eriu

m

110

Uun —

Unu

nnili

um

111

Uuu —

Unu

nuni

um

112

Uub —

Unu

nbiu

m

114

Uuq —

Unu

nqua

dium

116

Uuh —

Unu

nhex

ium

118

Uuo —

Unu

noct

ium

87 Fr[2

23.0

]Fr

anci

um

88 Ra

[226

.0]

Rad

ium

89–1

03

Act

inid

es

104

Rf

[261

.1]

Rut

herf

ordi

um

105

Db

[262

.1]

Dub

nium

106

Sg[2

63.1

]Se

abor

gium

57 La

138.

9L

anth

anum

89 Ac

[227

.0]

Act

iniu

m

1 H1.

008

Hyd

roge

n

Sym

bol o

f el

emen

t

Nam

e of

ele

men

t

PE

RIO

DIC

TA

BL

E O

F T

HE

EL

EM

EN

TS

KE

Y

2 He

4.00

3H

eliu

m

3 Li

6.94

1L

ithiu

m

4 Be

9.01

2B

eryl

lium

Ato

mic

Num

ber

Ato

mic

Wei

ght

79 Au

197.

0G

old

6 C12

.01

Car

bon

8 O16

.00

Oxy

gen

10 Ne

20.1

8N

eon

11 Na

22.9

9So

dium

12 Mg

24.3

1M

agne

sium

14 Si28

.09

Silic

on

16 S32

.07

Sulf

ur

18 Ar

39.9

5A

rgon

19 K39

.10

Pota

ssiu

m

20 Ca

40.0

8C

alci

um

21 Sc44

.96

Scan

dium

22 Ti

47.8

7T

itani

um

23 V50

.94

Van

adiu

m

24 Cr

52.0

0C

hrom

ium

25 Mn

54.9

4M

anga

nese

26 Fe55

.85

Iron

27 Co

58.9

3C

obal

t

28 Ni

58.6

9N

icke

l

29 Cu

63.5

5C

oppe

r

30 Zn

65.3

9Z

inc

32 Ge

72.6

1G

erm

aniu

m

34 Se78

.96

Sele

nium

36 Kr

83.8

0K

rypt

on

37 Rb

85.4

7R

ubid

ium

38 Sr87

.62

Stro

ntiu

m

39 Y88

.91

Yttr

ium

40 Zr

91.2

2Z

irco

nium

41 Nb

92.9

1N

iobi

um

42 Mo

95.9

4M

olyb

denu

m

43 Tc

[98.

91]

Tech

netiu

m

44 Ru

101.

1R

uthe

nium

45 Rh

102.

9R

hodi

um

46 Pd10

6.4

Palla

dium

47 Ag

107.

9Si

lver

48 Cd

112.

4C

adm

ium

50 Sn11

8.7

Tin

52 Te12

7.6

Tellu

rium

54 Xe

131.

3X

enon

55 Cs

132.

9C

aesi

um

56 Ba

137.

3B

ariu

m

57–7

1

Lan

than

ides

72 Hf

178.

5H

afni

um

73 Ta18

0.9

Tant

alum

74 W18

3.8

Tun

gste

n

75 Re

186.

2R

heni

um

76 Os

190.

2O

smiu

m

77 Ir19

2.2

Irid

ium

78 Pt19

5.1

Plat

inum

79 Au

197.

0G

old

80 Hg

200.

6M

ercu

ry

82 Pb20

7.2

Lea

d

84 Po[2

10.0

]Po

loni

um

86 Rn

[222

.0]

Rad

on

58 Ce

140.

1C

eriu

m

59 Pr14

0.9

Pras

eody

miu

m

60 Nd

144.

2N

eody

miu

m

61 Pm[1

46.9

]Pr

omet

hium

62 Sm 150.

4Sa

mar

ium

63 Eu

152.

0E

urop

ium

64 Gd

157.

3G

adol

iniu

m

65 Tb

158.

9Te

rbiu

m

66 Dy

162.

5D

yspr

osiu

m

67 Ho

164.

9H

olm

ium

68 Er

167.

3E

rbiu

m

69 Tm

168.

9T

huliu

m

70 Yb

173.

0Y

tterb

ium

71 Lu

175.

0L

utet

ium

90 Th

232.

0T

hori

um

91 Pa23

1.0

Prot

actin

ium

92 U23

8.0

Ura

nium

93 Np

[237

.0]

Nep

tuni

um

94 Pu[2

39.1

]Pl

uton

ium

95 Am

[241

.1]

Am

eric

ium

96 Cm

[244

.1]

Cur

ium

97 Bk

[249

.1]

Ber

keliu

m

98 Cf

[252

.1]

Cal

ifor

nium

99 Es

[252

.1]

Ein

stei

nium

100

Fm[2

57.1

]Fe

rmiu

m

101

Md

[258

.1]

Men

dele

vium

102

No

[259

.1]

Nob

eliu

m

103

Lr

[262

.1]

Law

renc

ium

Act

inid

es

Lan

than

ides

Whe

re th

e at

omic

wei

ght i

s no

t kno

wn,

the

rela

tive

atom

ic m

ass

of th

e m

ost c

omm

on r

adio

activ

e is

otop

e is

sho

wn

in b

rack

ets.

The

ato

mic

wei

ghts

of

Np

and

Tc

are

give

n fo

r th

e is

otop

es 23

7 Np

and

99T

c.

chemistry - lazsta - home03-08...2008 higher school certificate examination chemistry general...

Documents