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Pages: 12 Questions: 8 ©Copyright for part(s) of this examination may be held by individuals and/or organisations other than the Tasmanian Qualifications Authority.

PLACE LABEL HERE

Tasmanian Certificate of Education

CHEMISTRY

Senior Secondary

Subject Code: CHM315109

External Assessment

2009

Part 1

Time: approximately 45 minutes

On the basis of your performance in this examination, the examiners will provide a result on the following criteria taken from the syllabus statement: Criterion 5 Demonstrate an understanding of the fundamental principles and

theories of electrochemistry.

Criterion Mark

5 /40

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Chemistry – Part 1

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CANDIDATE INSTRUCTIONS Candidates MUST ensure that they have addressed ALL of the externally assessed criteria on this examination paper. Answer ALL questions (making sure you answer all parts within each question so that the criteria can be assessed). Answers must be written in the spaces provided on the examination paper. The 2009 Chemistry Information Sheet can be used throughout the examination. No other printed material is allowed into the examination. TQA approved graphics calculators can be used throughout the examination. Each booklet is of equal value (40 marks). This examination is 3 hours in length; it is recommended that you spend no more than 45 minutes on any one of the FOUR parts to this examination. In calculations no credit can be given for incorrect answers unless they are accompanied by details of the working. Some credit will be given for unsimplified answers. Appropriate units must be included.

NOTE: 1 litre (L) = 1000 millilitres (mL) = 1 dm3 = 1000 cm3. All written responses must be in English.


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Question 1 (a) List the oxidation states of chromium in the following compounds: (2 marks)

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Cr2O3 .................................................

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CrO2− ...........................................................

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CrCl2.H2O .........................................

€

Cr2O72− .......................................................

(b) Explain why the reaction

€

Zn(s) + S() → ZnS(s)

is an oxidation-reduction reaction whereas the precipitation reaction

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Zn2+(aq) + S2-(aq) → ZnS(s) is not an oxidation-reduction reaction. (2 marks) ............................................................................................................................................. ............................................................................................................................................. ............................................................................................................................................. .............................................................................................................................................


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Question 2 The iodide ion,

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I− , reacts with the iodate ion,

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IO3− , in acidic solution to form iodine,

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I2 . Write the two half equations, and hence the overall equation for this reaction. (3 marks) ...................................................................................................................................................... ...................................................................................................................................................... ...................................................................................................................................................... ...................................................................................................................................................... ...................................................................................................................................................... ...................................................................................................................................................... Question 3 A manufacturer of chrome plated car parts achieves the electroplating while passing the car parts through an acidified solution containing dichromate ions. The car parts are attached to the negative terminal of a power supply. The cell operates by using a steady current of 464 A for an 8.00 hour shift. The reduction equation is:

€

Cr2O72−(aq) + 14H+(aq) + 12e− → 2Cr(s) + 7H2O()

What mass of chromium metal can be plated during the 8.00 hour shift? (4 marks) ...................................................................................................................................................... ...................................................................................................................................................... ...................................................................................................................................................... ...................................................................................................................................................... ...................................................................................................................................................... ...................................................................................................................................................... ...................................................................................................................................................... ...................................................................................................................................................... ......................................................................................................................................................


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Question 4 (a) With reference to standard reduction potentials explain why zinc reacts with

1.00 mol

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L−1 sulfuric acid solution, but copper does not. (2 marks) ............................................................................................................................................. ............................................................................................................................................. ............................................................................................................................................. ............................................................................................................................................. (b) Copper will, however, react with 1.00 mol

€

L−1 nitric acid solution. Explain why and include the overall equation. (3 marks)

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


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Question 5 A solution containing 1.00 mol

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L−1 zinc chloride,

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ZnCl2 , and 1.00 mol

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L−1 cadmium bromide,

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CdBr2 , is electrolysed on the following electrolytic cell.

Pt electrode Pt electrode Solution containing 1.00 mol

€

L−1

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ZnCl2 and 1.00 mol

€

L−1

€

CdBr2

The voltage of the cell can be varied and is gradually increased. (a) What product should first appear at the anode? Explain. (2 marks) ............................................................................................................................................. ............................................................................................................................................. ............................................................................................................................................. ............................................................................................................................................. (b) What product should first appear at the cathode? Explain. (2 marks) ............................................................................................................................................. ............................................................................................................................................. ............................................................................................................................................. ............................................................................................................................................. (c) Describe one change to the electrolytic cell over time. (1 mark) ............................................................................................................................................. .............................................................................................................................................


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Question 6 Consider the following electrochemical cell:

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Mn(s) Mn2+(aq) MnO4−(aq)/H+(aq), Mn2+(aq) C(s)

On the diagram below label the anode and the cathode, write the anode and cathode reaction and overall reactions, and calculate the maximum E˚ (volts) for the cell. (4 marks)

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Mn(s)

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C(s)

Anode Reaction: ......................................................................................................................... Cathode Reaction: ....................................................................................................................... Overall Reaction: ........................................................................................................................ Max E˚: ....................................................................................................................................... ......................................................................................................................................................

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Question 7 An electrochemical cell is set up using the lead and copper standard half cells. (a) On the diagram below label the electrodes as positive or negative, and show the direction

of the electron flow. (1 mark)

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Cu(s)

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Pb(s)

(b) On the diagram label the salt bridge and discuss its role. (3 marks) ............................................................................................................................................. ............................................................................................................................................. ............................................................................................................................................. ............................................................................................................................................. ............................................................................................................................................. ............................................................................................................................................. (c) List suitable chemicals for each electrolyte and the salt bridge, giving a reason for each

choice. (3 marks) ............................................................................................................................................. ............................................................................................................................................. ............................................................................................................................................. ............................................................................................................................................. ............................................................................................................................................. .............................................................................................................................................

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Question 8 Iron is often manufactured with a coating of zinc, chromium or a non-conducting polymer. (a) Explain why such coatings are used. (1 mark) ............................................................................................................................................. ............................................................................................................................................. ............................................................................................................................................. (b) Discuss the effectiveness of each throughout the life of the iron product. (5 marks) ............................................................................................................................................. ............................................................................................................................................. ............................................................................................................................................. ............................................................................................................................................. ............................................................................................................................................. ............................................................................................................................................. ............................................................................................................................................. ............................................................................................................................................. ............................................................................................................................................. ............................................................................................................................................. ............................................................................................................................................. (c) Using a power source, how could an uncoated iron structure be protected? (2 marks) ............................................................................................................................................. ............................................................................................................................................. ............................................................................................................................................. .............................................................................................................................................


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PLACE LABEL HERE


CHEMISTRY

Senior Secondary


External Assessment

2009

Part 2


On the basis of your performance in this examination, the examiners will provide a result on the following criteria taken from the syllabus statement: Criterion 6 Demonstrate knowledge and understanding of the principles and

theories of thermochemistry, kinetics and equilibrium.

Criterion Mark

6 /40

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Question 9 Chlorine gas,

€

Cl2 , reacts with solid silver bromide, AgBr, as in the equation:

€

AgBr(s) + 1

2Cl2(g) → AgCl(s) + 1

2Br2()

€

ΔH = 28.7 kJ

€

mol-1

(a) Show the enthalpy of reactants and products and

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ΔH for this reaction on the axes below. (2 marks)

enthalpy kJ

€

mol-1 Reaction coordinate

(b) If 7.09 g of chlorine gas is consumed, calculate the heat change. (2 marks) ............................................................................................................................................. ............................................................................................................................................. ............................................................................................................................................. ............................................................................................................................................. Question 10 In a welder’s oxyacetylene torch, oxygen and acetylene (ethyne) are adjusted to get a steady flame. Why is this not a system in chemical equilibrium? (1 mark) ...................................................................................................................................................... ...................................................................................................................................................... ...................................................................................................................................................... ......................................................................................................................................................


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Question 11 A mixture of hydrogen and oxygen does not react at room temperature and pressure. However the mixture reacts explosively at these conditions when an electric spark is discharged in it. (a) Clearly explain the role of the electric spark and whether it is acting as a catalyst.

(2 marks) ............................................................................................................................................. ............................................................................................................................................. ............................................................................................................................................. ............................................................................................................................................. (b) Comment on the size of the activation energy and whether the reaction is endothermic or

exothermic. Explain. (2 marks) ............................................................................................................................................. ............................................................................................................................................. ............................................................................................................................................. .............................................................................................................................................


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Question 12 Some bond energies for bonds in gaseous molecules are listed below:

Bond type Bond energy (kJ

€

mol-1)

C–H 416

C=C 609

C–C 346

O–H 463

C–O 358

(a) Use the bond energies in the table, and your knowledge of chemical structures, to

calculate

€

ΔH for the dehydration of ethanol to ethene and water. (2 marks)

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CH3CH2OH(g) → CH2 = CH2(g) + H2O(g) ............................................................................................................................................. ............................................................................................................................................. ............................................................................................................................................. ............................................................................................................................................. ............................................................................................................................................. ............................................................................................................................................. ............................................................................................................................................. ............................................................................................................................................. (b) What does the result indicate about the reaction? (1 mark) ............................................................................................................................................. .............................................................................................................................................


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Question 13 The graph below shows the distribution of kinetic energies for reacting particles for a particular reaction at a temperature of

€

T1. The activation energy for the reaction is also indicated on the graph.

(a) On the graph above add the sketch showing the kinetic energy distribution of the same

particles at a higher temperature

€

T2. (1 mark) (b) Use your graph to help explain the effects of increasing temperature on reaction rate. (3 marks) ............................................................................................................................................. ............................................................................................................................................. ............................................................................................................................................. ............................................................................................................................................. ............................................................................................................................................. .............................................................................................................................................


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Question 14 Consider the following chemical equilibrium between carbon dioxide, carbon and carbon monoxide.

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CO2(g) + C(s)

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2CO(g)

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ΔH =171.5 kJ

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mol-1 (a) Explain the effect on the equilibrium position of adding more carbon to the system. (2 marks)

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

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

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

............................................................................................................................................. (b) Explain the pressure and temperature conditions that maximise the yield of

€

CO(g). (4 marks)

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

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

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Question 14 continues opposite.


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Question 14 (continued) (c) Explain how the following changes affect the rate of the forward reaction: (4 marks) (i) decreasing the volume of the reaction vessel; .................................................................................................................................... .................................................................................................................................... .................................................................................................................................... .................................................................................................................................... (ii) using larger pieces of

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C(s) . .................................................................................................................................... .................................................................................................................................... .................................................................................................................................... .................................................................................................................................... (d) What effect would adding a catalyst have on the rate of forward reaction and on the

equilibrium position? (2 marks)

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

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

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Question 15 A compound A has two competing reactions:

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A → B or

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A → C The graph below shows how the rates of formation of B and C change with temperature.

(a) What temperature range will give a greater concentration of product B, compared to

product C? (1 mark)

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

............................................................................................................................................. (b) What is the approximate ratio of products B to C at temperature

€

T2? (1 mark)

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

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

€

T1

€

T2

€

T3

€

T4

€

T5


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Question 16 A laboratory technician prepared a solution of hydrofluoric acid, HF, a weak monoprotic acid. She dissolved 0.100 mol of HF in water and made the volume up to 1.000 L in a volumetric flask. (a) When equilibrium was achieved the concentration of both

€

H+(aq) and

€

F−(aq) was 0.025 mol

€

L−1. Determine the actual concentration of

€

HF(aq) molecules when equilibrium was achieved and hence calculate the value of

€

Ka for hydrofluoric acid. (3 marks)

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

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

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

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

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Question 16 continues over the page.


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Question 16 (continued) (b) On the graph below show the changes in the concentrations of

€

HF(aq) ,

€

H+(aq) and

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F−(aq) from when the solution is first made until equilibrium is achieved at

€

T1.

Ensure your graph is labelled and distinguishes between

€

HF(aq) ,

€

H+(aq) and

€

F−(aq). (3 marks)


€

T3

€

T1

€

T2


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Question 16 (continued) (c) At

€

T2 the laboratory technician adds some

€

HCl(aq) to the equilibrium so that the total

€

H+(aq) concentration rises immediately to 0.05 mol

€

L−1. Assume there is negligible volume change on addition of the HCl. Continue your graph from

€

T1 past time

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T2 showing how the concentrations of the three species

€

HF(aq) ,

€

H+(aq) and

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F−(aq) change until the new equilibrium is established at

€

T3.

Calculations of exact final concentrations are not required for this part. Give reasons for the changes shown after

€

T2. (4 marks)

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PLACE LABEL HERE


CHEMISTRY

Senior Secondary


External Assessment

2009

Part 3


On the basis of your performance in this examination, the examiners will provide a result on the following criteria taken from the syllabus statement: Criterion 7 Demonstrate knowledge and understanding of the properties

and reactions of organic and inorganic matter.

Criterion Mark

7 /40

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Question 17 The electronic configuration of an element is:

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1s22s22p63s23p63d104s24p64d104f145s25p65d106s26p3 (a) What is the atomic number and name of the element? (1 mark) Atomic number:................................................................................................................ Name: ............................................................................................................................. (b) The last electrons in the configuration are

€

6s26p3. Explain what the number, 6, and the letters, s and p, represent. (2 marks)

.......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... Question 18 Complete the following table: (3 marks)

Atoms/ions nuclear charge on both Atom/ion with greater radius

(a) B, C

(b)

€

F− ,

€

O2−


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Question 19 (a) The successive ionisation energies for lithium are: 0.526 MJ

€

mol-1 , 7.30 MJ

€

mol-1 and 11.8 MJ

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mol-1

Explain this variation. (3 marks)

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


Ionisation Energies of Lithium

Ionisation

1 2 3 Ioni

satio

n En

ergy

MJ m

ol–1

0

3

6

9

12


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Question 19 (continued) (b) The first ionisation energies of the alkaline earth metals are:

magnesium, 0.744 MJ

€

mol-1 , calcium, 0.596 MJ

€

mol-1 , and strontium, 0.556 MJ

€

mol-1 . Hence explain the trend in reactivity from Mg to Sr. (3 marks)

.......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... (c) Discuss the trend in the reactivity of the metals, Na, Mg and Al, and explain in terms of

the electron configurations. (2 marks) .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... ..........................................................................................................................................

Ionisation Energies of alkaline earth metals

Mg Ca Sr

1

0

0.50

0.25

0.75

MJ m

ol–1


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Question 20 Discuss the reactivity of benzene,

€

C6H6, and cyclohexene,

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C6H10, with chlorine. List the organic product of each reaction. (3 marks) ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ...................................................................................................................................................


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Question 21 Complete the following table: (3 marks)

Name Structural formula Structural formula of organic compound

formed in reaction with sodium

pentan-2-ol

Name Structural formula Functional group present

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CH3CH2CH2CH2CCH3

C – O – H

O

O


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Question 22 (a) The cycloalkene 3,3-dimethylcyclohexene reacts with hydrogen bromide, HBr.

There are two possible isomers formed. Fill in all the structural formulae for the reactions below and name one of the

products. (2 marks)

+ HBr (b) The synthetic polymer polystyrene is a versatile polymer and is used for making

yoghurt containers, refrigerator doors, shoe heels and wall tiles. The monomer has the structural formula:

€

CH = CH2

Draw three units of the polymer, polystyrene. (1 mark)

3,3-dimethylcyclohexene


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Question 23 Two organic compounds containing carbon, hydrogen and oxygen have a molar mass of 58.078 g

€

mol-1 and are known to contain 1 oxygen atom only. Nuclear magnetic resonance spectroscopy shows the presence of at least one methyl group in each, and no C = C. Determine the molecular formula of the isomers and hence their structural formulae and names. (3 marks) ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... Question 24 Consider the following liquids that can be produced from the gaseous hydrocarbon, ethane,

€

C2H6: ethanol

€

CH3CH2OH ethan-1,2-diol

€

CH2OH

€

CH2OH ethanal

€

CH3CHO Using your knowledge of bonding, rank the liquids in order of increasing boiling points. Explain your choice and why they have a much higher boiling point than ethane. (3 marks) ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... ...................................................................................................................................................


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Question 25 Two isomers of

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C4H9Cl underwent a series of reactions shown in the flowchart below: (a) Identify compounds A and B, clearly explaining your reasons. (4 marks) .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... ..........................................................................................................................................


forms compound E

no reaction occurred

An isomer of C4H9Cl Compound D

reaction with sodium hydroxide NaOH

reacted with acidified

€

KMnO4

forms compound A

forms compound B has pH < 7

forms compound C a sweet smelling liquid

1-chloro-2-methylpropane C4H9Cl

reaction with sodium hydroxide NaOH

reacted with acidified

€

KMnO4

Reacted with compound A in Presence of concentrated

€

H2SO4


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Question 25 (continued) (b) Write balanced equations (half equations and the overall equation) for the oxidation

of compound A to compound B. (2 marks) .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... (c) Name the functional group in compound C, draw its structural formula and indicate

its expected solubility in water. (2 marks) Functional group: ........................................................................................................... Structural formula: Solubility in water: ......................................................................................................... (d) Deduce the structure of compound D. Clearly explain your reasons. (2 marks) .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... (e) Name of compound E: ...................................................................................... (1 mark)


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PLACE LABEL HERE


CHEMISTRY

Senior Secondary


External Assessment

2009

Part 4


On the basis of your performance in this examination, the examiners will provide a result on the following criteria taken from the syllabus statement: Criterion 8 Apply logical processes to solve quantitative chemical

problems.

Criterion Mark

8 /40

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Question 26 A 0.254 g sample of black coal was burnt in a bomb calorimeter. The calorimeter contained 300.0 mL of water, which rose in temperature from 18.25˚C to 24.92˚C. (a) Calculate the heat absorbed by the water and hence the heat of combustion

of the coal in kJ

€

g−1. (Assume the heat absorbed by the calorimeter is negligible.) (2 marks) .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... (b) Is your answer likely to be higher or lower than the actual value? Explain. (2 marks) .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... Question 27 Tools in a sea water aquarium had acquired an estimated 50 g of rust,

€

Fe2O3. The rust was removed by treatment with oxalic acid,

€

H2C2O4 , according to the following equation.

€

Fe2O3(s) + 6H2C2O4(aq) → 2Fe C2O4( )33-(aq) + 6H+(aq)

Calculate the minimum volume of a 2.00 mol

€

L-1 solution of oxalic acid that would be required to remove 50.0 g of rust. (4 marks) ...................................................................................................................................................

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Question 28 The Bureau of Meteorology release large balloons daily to measure atmospheric conditions. At remote stations water is converted to hydrogen for the balloon gas. (a) A balloon of volume 1050 L was released in Antarctica to study upper atmosphere

ozone depletion.

The temperature at ground level was –41˚C and the atmospheric pressure 100.3 kPa. The balloon rose to a height of 20 km where the temperature was –50˚C and the atmospheric pressure 25.0 kPa.

Calculate the volume at this height. (3 marks) .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... ..........................................................................................................................................



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Question 28 (continued) (b) The hydrogen gas is obtained from water according to the equation

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2H2O() → 2H2(g) + O2(g) A different sized balloon was filled with hydrogen at the Cape York station where

the temperature was 41˚C and the atmospheric pressure 103.7 kPa. (i) Calculate the mass of hydrogen obtained from 909 g of water, if the hydrogen

collection efficiency is 90%. (2 marks) .................................................................................................................................... .................................................................................................................................... .................................................................................................................................... .................................................................................................................................... (ii) Calculate the volume of a balloon when filled with 45.0 g of hydrogen at Cape

York. (2 marks) .................................................................................................................................... .................................................................................................................................... .................................................................................................................................... .................................................................................................................................... (iii) What mass of helium is required to give the same volume as the balloon in part

(ii) at Cape York? (1 mark) .................................................................................................................................... .................................................................................................................................... .................................................................................................................................... ....................................................................................................................................


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Question 29 (a) Calculate the pH of a solution made up of 200.0 mL of 0.1000 mol

€

L−1 solution of hydrochloric acid and 150.0 mL of 0.200 mol

€

L−1 solution of potassium hydroxide solution. (4 marks)

.......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... (b) Methanoic acid, HCOOH, has

€

Ka = 2.10 ×10−4 at 25˚C. Calculate the pH of a 0.500 mol

€

L−1 aqueous solution of methanoic acid at 25˚C. (4 marks) .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... ..........................................................................................................................................


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Question 30 Calculate

€

ΔH for the heat of formation of ethane from graphite and hydrogen gas according to the equation:

€

2C(s, graphite) + 3H2(g) → C2H6(g) Given the following data about combustion reactions: (3 marks)

€

C(s, graphite) + O2(g) → CO2(g)

€

ΔH = -393 kJ mol

€

−1

€

H2(g) + 1

2O2(g) → H2O()

€

ΔH = -285 kJ mol

€

−1

€

C2H6(g) + 72

O2(g) → 2CO2(g) + 3H2O ( )

€

ΔH = -1560 kJ mol

€

−1

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Question 31 A gold purification process uses the following reactions. Impure gold is reacted with potassium cyanide, KCN, forming the compound KAu(CN)2. This is then treated with zinc. The reaction is:

€

2KAu(CN)2 + Zn → K2Zn(CN)4 + 2Au 3.90 kg of

€

KAu(CN)2 was reacted with 1.10 kg of Zn. (a) Calculate the maximum mass of pure gold which could be obtained from this

reaction. (4 marks) .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... (b) What mass of the reagent in excess is left over after the reaction is complete? (2 marks) .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... ..........................................................................................................................................


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Question 32 The alcohol (ethanol,

€

C2H5OH ) content of wine can be found by titration with standardised acidified potassium dichromate,

€

K2Cr2O7 , solution. Equations representing the essential reactions are:

€

3C2H5OH() + 2Cr2O72−(aq) + 16H+(aq) → 3CH3COOH(aq) + 4Cr3+(aq) + 11H2O()

To do this a 50.00 mL sample of wine was diluted to 1000.0 mL in a volumetric flask. 25.00 mL samples of the diluted wine required 15.50 mL of 0.1160 mol

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L−1 acidified potassium dichromate solution to reach the end point. Assume that the potassium dichromate reacts with the alcohol only. (a) Calculate the concentration of alcohol in the original sample of wine. (5 marks) .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... (b) What is the mass/mass percentage of ethanol in the wine if the wine has a density of

0.9850 g m

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L−1? (2 marks) .......................................................................................................................................... .......................................................................................................................................... .......................................................................................................................................... ..........................................................................................................................................


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PLACE LABEL HERE - tqa.tas.gov.au€¦ · NOTE: 1 litre (L) = 1000 millilitres ... The voltage of...

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