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INSTRUCTIONS AND INFORMATION -
1. Answer ALL questions
2. Question paper consists of TWO sections: SECTION A (25) SECTION B (125)
3. You may use a non-programmable calculator
4. Use appropriate mathematical instruments
5. Use appropriate mathematical instruments
6. Round off your final numerical answers to a minimum of TWO decimal place

QUESTION 1; ONE WORD ITEMS -
Give ONE word/term for each of the following descriptions. Write only the word/term next to the question

Marks: 5

Question 1:

The homologous series to which compounds with the functional group –OH belong

Your Answer:

Question 2:

The process in which large alkane molecules are broken up into smaller alkanes and alkenes

Your Answer:

Question 3:

The amount of products formed or reactants used per unit time in a chemical reaction

Your Answer:

Question 4:

The process in which electricity is used to decompose a chemical substance

Your Answer:

Question 5:

The name of the industrial process used in the production of ammonia

Your Answer:

QUESTION 2; MULTIPLE-CHOICE QUESTIONS -
Four options are provided as possible answers to the following questions. Each question has only ONE correct answer. Write only the letter (A–D)

Marks: 20

Question 1:

Which ONE of the following compounds has the highest melting point?

Attached Resource:

14ca4595-3f5a-4e1a-ab41-c41ed79b4584.PNG

Your Answer:

A

B

C

D

Question 2:

Which of the compounds above are structural isomers?

Attached Resource:

aa22fe4d-dfbb-4c8d-ab02-fc88fe8498ae.png

Your Answer:

I and II

I and III

I and IV

II and III

Question 3:

This reaction is an example of …

Attached Resource:

98276fda-4653-4519-b95c-a41d23ddf27c.png

Your Answer:

addition.

oxidation

elimination

substitution.

Question 4:

Activation energy can best be described as the minimum energy required to …

Your Answer:

cause effective collisions

make reactant molecules collide.

increase the kinetic energy of reactant molecules.

change the orientation of reactant molecules.

Question 5:

Which ONE of the following CORRECTLY describes the effect of an INCREASE IN TEMPERATURE on a reaction at equilibrium?

Attached Resource:

513d3359-f8c0-40da-b2cf-5de6183b4096.png

Your Answer:

A

B

C

D

Question 6:

Each of the reactions represented below is at equilibrium in a closed container. In which ONE of these reactions will an INCREASE IN PRESSURE (by decreasing the volume) favour the formation of products?

Attached Resource:

17157f8b-146a-4e94-82e5-c2fb748d3b66.PNG

Your Answer:

A

B

C

D

Question 7:

Which ONE of the following half-reactions occurs at the CATHODE during the electrolysis of a solution of CuCℓ2?

Attached Resource:

b94c875e-c7d7-48ad-a6fa-a13566e69aaa.PNG

Your Answer:

A

B

C

D

Question 8:

When a galvanic (voltaic) cell delivers current, the salt bridge …

Your Answer:

allows electrons to move in the cell

ensures electrical neutrality in the cell.

prevents the two solutions from mixing.

allows electrons to travel from the cathode to the anode.

Question 9:

Which ONE of the following metals is the strongest reducing agent?

Your Answer:

Ag

Zn

Cu

Aℓ

Question 10:

The chlor-alkali process leads to the production of two gases. Which ONE of the following CORRECTLY shows the gases produced at the anode and cathode of this cell?

Attached Resource:

87564806-7142-45e2-8b1a-be96a5c64f9f.png

Your Answer:

A

B

C

D

SECTION B -
INSTRUCTIONS
1. Show the formulae and substitutions in ALL calculations.
2. Round off your final numerical answers to a minimum of TWO decimal places.

QUESTION 3

Attached Section Resource:

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QUESTION 3,1 -
Write down the letter representing the compound which: (A compound may be used more than once.)

Marks: 6

Question 1:

Is an aldehyde

Your Answer:

Question 2:

Has the general formula C_nH_2n

Your Answer:

Question 3:

Is unsaturated

Your Answer:

Question 4:

Is a ketone

Your Answer:

Question 5:

Is a hydrocarbon

Your Answer:

Question 6:

Can be prepared by the reaction of an alcohol with a carboxylic acid

Your Answer:

QUESTION 3,2 - Write down the structural formula of:

Marks: 4

Question 1:

Compound A

Your answer: Resource(s)

Question 2:

Compound D

Your answer: Resource(s)

QUESTION 3.3 - Write down the following:

Marks: 3

Question 1:

NAME of the functional group of compound F

Your Answer:

Question 2:

IUPAC name of compound B

Your Answer:

QUESTION 4

Attached Section Resource:

4140aa7b-a951-4550-b278-83fe4bfd575c.png

QUESTION 4.1 - Compound A is used as a fuel in gas burners.

Marks: 10

Question 1:

Is compound A in the GAS, LIQUID or SOLID phase at 25 °C?

Your Answer:

Question 2:

How will the boiling point of an ISOMER of compound A compare to that of compound A? Write down HIGHER THAN, LOWER THAN or EQUAL TO. Refer to MOLECULAR STRUCTURE,
INTERMOLECULAR FORCES and the ENERGY needed to explain the answer.

Your Answer:

Question 3:

Using molecular formulae, write down the balanced equation for the combustion of compound A in excess oxygen.

Your Answer:

Question 4:

Compound A has a lower boiling point than compound B. Give reasons for this difference in boiling points by referring to the following:

• Structural differences between the two compounds
• Polarity

Your Answer:

QUESTION 4.2 - Consider the boiling points of compounds C and D.

Marks: 4

Question 1:

Give a reason for this difference in boiling points by referring to the intermolecular forces present in EACH of these compounds.

Your Answer:

Question 2:

Which ONE of compound C or D has a higher vapour pressure?
Refer to their boiling points to give a reason for the answer.

Your Answer:

QUESTION 5

Marks: 1

Attached Section Resource:

d9cc6c3f-6195-4d6b-95b4-f5e24a8d967e.png

Question 1:

Is butan-1-ol a PRIMARY, SECONDARY or TERTIARY alcohol?

Your Answer:

QUESTION 5.2 - Product P is formed when butan-1-ol is heated in the presence of concentrated sulphuric acid.
Write down the following:

Marks: 6

Question 1:

Name of the type of reaction that takes place

Your Answer:

Question 2:

Balanced equation for the reaction that takes place using structural formulae

Your answer: Resource(s)

QUESTION 5.3 - Product R is formed when butan-1-ol reacts with ethanoic acid in the presence of an acid catalyst.
Write down the following:

Marks: 3

Question 1:

Name of the type of reaction that takes place

Your Answer:

Question 2:

Structural formula of the organic product formed

Your answer: Resource(s)

QUESTION 5.4 - When HBr reacts with butan-1-ol, compound Q, a haloalkane, is formed.
Write down the following:

Marks: 3

Question 1:

Name of the type of reaction that takes place

Your Answer:

Question 2:

IUPAC name of the haloalkane formed

Your Answer:

QUESTION 6

Marks: 2

Attached Section Resource:

9eea9cee-d29f-4a3c-8eaa-1a594406fd16.png

Question 1:

Write down the name of the flask labelled Z.

Your Answer:

Question 2:

Write down ONE function of the item of apparatus labelled Y in THIS investigation.

Your Answer:

QUESTION 6.3 - FROM THE TABLE, write down the following:

Marks: 2

Attached Section Resource:

7ae7b895-10c9-4c32-9fb7-ec08b23680bc.png

Question 1:

The independent variable for this investigation

Your Answer:

Question 2:

ONE controlled variable

Your Answer:

QUESTION 6.4

Marks: 3

Attached Section Resource:

b84bb063-7b03-451e-86cf-d690aa9feb2a.png

Question 1:

Which graph, P or Q, represents Experiment 2? Refer to the data given in the table, as well as the shape of the graph, to explain how you arrived at the answer

Your Answer:

QUESTION 6.5

Marks: 1

Question 1:

Give a reason why the rate of hydrogen production slows down towards the end in both experiments.

Your Answer:

QUESTION 6.6

Marks: 6

Question 1:

Calculate the mass of zinc used to prepare 0,24 dm³ of hydrogen gas at room temperature. Assume that 1 mole of hydrogen gas has a volume of 24,04 dm³ at room temperature.

Your Answer:

QUESTION 7

Attached Section Resource:

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QUESTION 7.1

Marks: 2

Question 1:

Is this reaction exothermic or endothermic? Give a reason for the answer.

Your Answer:

QUESTION 7.2 - The graphs below, not drawn to scale, show how the amounts of reactants present in the container change with time at a specific temperature. The volume of the container is 5 dm3 .

Marks: 12

Attached Section Resource:

03c8e649-f99c-460f-a277-47af171bbf25.png

Question 1:

How does the rate of the forward reaction at time t1 compare to that at time t2? Write down GREATER THAN, SMALLER THAN or EQUAL TO. Use the graphs to give a reason for the answer.

Your Answer:

Question 2:

How does the rate of the forward and the reverse reactions compare at time t₃? Write down only GREATER THAN, SMALLER THAN or EQUAL TO.

Your Answer:

Question 3:

Calculate the equilibrium constant (K_c) for this reaction at this temperature.

Your Answer:

QUESTION 7.3 - The temperature is NOW increased. How will this change affect the value of the equilibrium constant?

Marks: 4

Question 1:

Write down INCREASES, DECREASES or REMAINS THE SAME. Explain the answer.

Your Answer:

QUESTION 7.4 - How will each of the following changes affect the equilibrium concentration of Cℓ2(g)? Write down INCREASES, DECREASES or REMAINS THE SAME.

Marks: 3

Question 1:

Water vapour is added into the container.

Your Answer:

Question 2:

A catalyst is added.

Your Answer:

Question 3:

The volume of the container is increased.

Your Answer:

QUESTION 8

Marks: 17

Attached Section Resource:

54eaf1be-2190-4e6f-9262-7796c358b106.png

Question 1:

Apart from concentration, write down TWO other conditions needed for the hydrogen half-cell to function at standard conditions.

Your Answer:

Question 2:

Write down the name of the item of apparatus labelled X.

Your Answer:

Question 3:

Is magnesium the ANODE or CATHODE in the cell above? Refer to the relative strengths of reducing agents to explain the answer.

Your Answer:

Question 4:

Write down the cell notation for this cell.

Your Answer:

Question 5:

Calculate the standard reduction potential of the magnesium half-cell. Show ALL your working.

Your Answer:

Question 6:

Write down the balanced NET (overall) cell reaction that takes place in this cell. No spectator ions are required.

Your Answer:

QUESTION 9

Attached Section Resource:

fa474750-dc0f-4469-96f8-b6ef2d01b118.png

QUESTION 9.1

Marks: 1

Question 1:

Write down the name of the type of electrochemical cell (ELECTROLYTIC or
GALVANIC) of which the above two cells are examples.

Your Answer:

QUESTION 9.2 - Pure copper is used as one of the electrodes in each of the cells above. In which cell (A or B) is the pure copper the:

Marks: 2

Question 1:

Cathode

Your Answer:

Question 2:

Anode

Your Answer:

QUESTION 9.3 - Consider cell B. Initially the CuSO4(aq) has a blue colour.

Marks: 5

Question 1:

How will the intensity of the blue colour change whilst the cell is functioning? Write down INCREASES, DECREASES or REMAINS
THE SAME. Give a reason for the answer.

Your Answer:

Question 2:

Write down the half-reaction that takes place at the pure copper electrode.

Your Answer:

QUESTION 9.4 - Consider cell A.

Marks: 3

Question 1:

Give a reason why the sludge formed in this cell is of economic importance.

Your Answer:

Question 2:

Name ONE negative impact that the energy usage in this process has on the environment.

Your Answer:

QUESTION 10

Attached Section Resource:

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QUESTION 10.1

Marks: 1

Question 1:

Write down the general name given to cells that are rechargeable.

Your Answer:

QUESTION 10.2

Marks: 2

Question 1:

Write down the balanced net (overall) cell reaction that takes place in this cell.

Your Answer:

QUESTION 10.3 - The emf of one such cell is 1,65 V and its capacity is 1 500 mA∙h.

Marks: 6

Question 1:

Define the term cell capacity.

Your Answer:

Question 2:

Calculate the maximum electrical work that can be done by this cell.

Your Answer:

QUESTION 11

Attached Section Resource:

aaa441ba-6aba-425c-9c5b-ce446cacca88.png

QUESTION 11.1 - Write down the NAME or FORMULA of:

Marks: 3

Question 1:

Gas A

Your Answer:

Question 2:

Gas B

Your Answer:

Question 3:

Fertiliser F

Your Answer:

QUESTION 11.2 - Sulphuric acid is used to prepare fertiliser C.
Write down the following

Marks: 4

Question 1:

The name of the industrial process used to prepare sulphuric acid

Your Answer:

Question 2:

A balanced equation for the preparation of fertiliser C

Your Answer:

QUESTION 11.3 - Gases D and E are prepared during the Ostwald process.
Write down the following:

Marks: 5

Question 1:

Name given to the preparation of gas D from ammonia

Your Answer:

Question 2:

Balanced equation for the preparation of gas D

Your Answer:

Question 3:

NAME or FORMULA of gas E

Your Answer: