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INSTRUCTIONS AND INFORMATION -
1.Answer ALL the questions.
2. This question paper consists of TWO sections:
SECTION A and SECTION B
3.Use a non-programmable calculator.
4.Use appropriate mathematical instruments.
5.Data sheets and a periodic table are attached for your use
6.Round off final numericals to two decimal places

SECTION A

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

Marks: 5

Question 1:

The industrial preparation of nitrogen gas from liquid air

Your Answer:

Question 2:

The removal of water from a compound during a reaction

Your Answer:

Question 3:

A theory used to explain how factors, such as temperature, change the rate of
a reaction

Your Answer:

Question 4:

The general term used to describe a substance that donates electrons to
another substance

Your Answer:

Question 5:

The general term used to describe a class of organic compounds in which
one member differs from the previous one by a CH2 group

Your Answer:

QUESTION 2 - MULTIPLE-CHOICE QUESTIONS

Marks: 20

Question 1:

Which ONE of the following is the functional group of aldehydes?

Your Answer:

─ COO ─

─ COOH

─ CHO

─ OH

Question 2:

Which ONE of the following hydrocarbons always gives a product with the same IUPAC name when ANY ONE of its hydrogen atoms is replaced with a chlorine atom?

Your Answer:

Hexane

Hex-1-ene

Cyclohexane

Cyclohexene

Question 3:

Which ONE of the following is the correct IUPAC name for compound X?

Attached Resource:

ffb3a1f0-217b-41b9-9025-ff08d61d2645.png

Your Answer:

Prop-1-ene

Prop-2-ene

Propan-1-ol

Propan-2-ol

Question 4:

The graphs represent the molecular distribution for a reaction at different temperatures.

Which ONE of the graphs above represents the reaction at the highest temperature?

Attached Resource:

17fe4177-db3c-4598-a50b-23b4bdefb23e.png

Your Answer:

P

Q

R

S

Question 5:

The reaction represented below reaches equilibrium in a closed container.

CuO(s) + H₂(g) ⇌ Cu(s) + H₂O(g) ∆H < 0

Which ONE of the following changes will increase the yield of products?

Your Answer:

Increase temperature.

Decrease temperature

Increase pressure by decreasing the volume.

Decrease pressure by increasing the volume

Question 6:

The graph below represents the decomposition of N₂O₄(g) in a closed container according to the following equation:

Which ONE of the following correctly describes the situation at t1?

Attached Resource:

30128800-e77d-45ed-8b7d-c3635ae0525d.png

Your Answer:

The N2O4 gas is used up.

The NO2 gas is used up.

The rate of the forward reaction equals the rate of the reverse reaction.

The concentrations of the reactant and the product are equal.

Question 7:

Which ONE of the following is the strongest oxidising agent?

Your Answer:

F2(g)

F- (aq)

Li(s)

Li+ (aq)

Question 8:

Which ONE of the following statements about a galvanic cell in operation is
CORRECT?

Your Answer:

∆H for the cell reaction is positive

The overall cell reaction is non-spontaneous.

The emf is negative

∆H for the cell reaction is negative.

Question 9:

The function of the salt bridge in a galvanic cell in operation is to ...

Your Answer:

allow anions to travel to the cathode

maintain electrical neutrality in the half-cells.

allow electrons to flow through it.

provide ions to react at the anode and cathode.

Question 10:

The major product formed at the ANODE in a membrane cell is .

Your Answer:

hydrogen.

oxygen

chlorine

hydroxide ions.

SECTION B -
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:

6165d7fe-9637-4e2e-896c-f29700712a73.png

QUESTION 3.1 -
Write down the letter(s) that represent(s) the following:

Marks: 6

Question 1:

Alkenes

Your Answer:

Question 2:

A ketone

Your Answer:

Question 3:

A compound with the general formula CnH2n-2

Your Answer:

Question 4:

A structural isomer of cyclohexene

Your Answer:

QUESTION 3.2 -
Write down the IUPAC name of compound:

Marks: 6

Question 1:

A

Your Answer:

Question 2:

E

Your Answer:

Question 3:

F

Your Answer:

QUESTION 3.3 -
Compound D is prepared by reacting two organic compounds in the presence of an acid as catalyst.
Write down the following:

Marks: 5

Question 1:

Homologous series to which compound D belongs

Your Answer:

Question 2:

Structural formula of compound D

Your answer: Resource(s)

Question 3:

IUPAC name of the organic acid used to prepare compound D

Your Answer:

Question 4:

NAME or FORMULA of the catalyst used

Your Answer:

QUESTION 4

Attached Section Resource:

98120f99-1cc1-4196-ba6a-a80c65b11b97.png

QUESTION 4.1 -
For this investigation, write down the following:

Marks: 2

Question 1:

Independent variable

Your Answer:

Question 2:

Dependent variable

Your Answer:

QUESTION 4.2

Marks: 1

Question 1:

From the passage above REFER question 4, write down a phrase that shows that this
investigation is a fair test.

Your Answer:

QUESTION 4.3 -
Which sample (P, Q or R) is the:

Marks: 4

Question 1:

Alkane

Your Answer:

Question 2:

Alcohol

Your Answer:

Question 3:

Refer to boiling point and the type of intermolecular forces present between alcohol molecules to give a reason for the answer in
QUESTION 4.3.2

Your Answer:

QUESTION 4.4

Marks: 4

Question 1:

The alkane is identified as pentane. Will the boiling point of hexane be HIGHER THAN or LOWER THAN that of pentane? Refer to MOLECULAR STRUCTURE, INTERMOLECULAR FORCES and ENERGY needed to explain the answer.

Your Answer:

QUESTION 5 -
Two straight chain compounds, P and Q, each have the following molecular formula: P: C4H10 Q: C4H8

QUESTION 5.1

Marks: 1

Question 1:

Write down the name of the homologous series to which Q belongs

Your Answer:

QUESTION 5.2 -
Compound P reacts with chlorine to form 2-chlorobutane. Write down the following :

Marks: 6

Question 1:

A balanced chemical equation, using MOLECULAR FORMULAE, for the reaction that takes place₂

Your Answer:

Question 2:

The type of reaction that takes place

Your Answer:

Question 3:

One reaction condition (other than the solvent needed)

Your Answer:

Question 4:

One reaction condition (other than the solvent needed)

Your Answer:

QUESTION 5.3 -
Compound Q takes part in reactions as shown in the flow diagram below.
Write down the:

Marks: 9

Attached Section Resource:

d74762cb-231e-47bb-9f37-f189ae4a31d6.png

Question 1:

Structural formula for 2,3-dibromobutane

Your answer: Resource(s)

Question 2:

IUPAC name of compound Q

Your Answer:

Question 3:

Balanced equation, using structural formulae, for reaction 1

Your answer: Resource(s)

Question 4:

Type of reaction that occurs in reaction 1

Your Answer:

QUESTION 6

Attached Section Resource:

525632e2-cc3d-4b6f-a3b9-dec1f49578f0.png

QUESTION 6.1 - For this investigation, write down the:

Marks: 2

Question 1:

Independent variable

Your Answer:

Question 2:

Dependent variable

Your Answer:

QUESTION 6.2 -
The results obtained are shown in the graph below.

Marks: 2

Attached Section Resource:

aa69feba-6079-4a87-a17a-7c3c96366667.png

Question 1:

Which catalyst is the most effective? Give a reason for the answer.

Your Answer:

QUESTION 6.3

Marks: 3

Question 1:

Fully explain, by referring to the collision theory, how a catalyst increases the rate of a reaction.

Your Answer:

QUESTION 6.4

Marks: 3

Attached Section Resource:

4393dc8c-76bb-4605-a8b2-8588b5a7d72c.png

Question 1:

Calculate the AVERAGE rate of decomposition (in mol∙dm-3·s-1) of H2O2(aq) in the first 400 s.

Your Answer:

QUESTION 6.5

Marks: 2

Question 1:

Will the rate of decomposition at 600 s be GREATER THAN, LESS THAN or EQUAL TO the rate calculated in QUESTION 6.4? Give a reason for the answer.

Your Answer:

QUESTION 6.6

Marks: 5

Question 1:

Calculate the mass of oxygen produced in the first 600 s if 50 cm³ of hydrogen peroxide decomposes in this time interval.

Your answer: Resource(s)

QUESTION 7

Marks: 10

Attached Section Resource:

19dd6428-54a8-4a52-8cfd-65d02dd3c2f9.png

Question 1:

Is the yield of NO(g) at temperature T HIGH or LOW? Give a reason for the answer.

Your Answer:

Question 2:

Calculate the equilibrium concentration of NO(g) at this temperature.

Your Answer:

QUESTION 7.1

QUESTION 7.2

QUESTION 7.3 -
How will each of the following changes affect the YIELD of NO(g)? Write down only INCREASES, DECREASES or REMAINS THE SAME.

Marks: 2

Question 1:

The volume of the reaction vessel is decreased at constant temperature.

Your Answer:

Question 2:

An inert gas such as argon is added to the mixture.

Your Answer:

QUESTION 7.4

Marks: 3

Question 1:

It is found that K_C of the reaction increases with an increase in temperature.
Is this reaction exothermic or endothermic? Explain the answer.

Your Answer:

QUESTION 8

Attached Section Resource:

033dae0a-8193-4824-a046-e73d1cf5efc8.png

QUESTION 8.1 -
Write down the:

Marks: 6

Question 1:

NAME or FORMULA of the oxidising agent

Your Answer:

Question 2:

Half-reaction which takes place at the anode

Your Answer:

Question 3:

Cell notation for this cell

Your Answer:

QUESTION 8.2

Marks: 4

Question 1:

Calculate the standard reduction potential of Au.

Your Answer:

QUESTION 8.3 -
Switch S is now closed and the bulb lights up.

Marks: 2

Question 1:

How will the reading on the voltmeter now compare to the INITIAL reading of 0,14 V? Write down only LARGER THAN, SMALLER THAN or EQUAL TO.
Give a reason for the answer.

Your Answer:

QUESTION 9

Attached Section Resource:

66b59c0f-3fb2-4a64-a293-606aad4e183c.png

QUESTION 9.1

Marks: 2

Question 1:

Define the term electrolysis

Your Answer:

QUESTION 9.2 -
Write down the following:

Marks: 4

Question 1:

Half-reaction that occurs at the spanner

Your Answer:

Question 2:

NAME or FORMULA of the metal of which electrode X is made

Your Answer:

Question 3:

NAME or FORMULA of the oxidising agent

Your Answer:

QUESTION 9.3

Marks: 4

Question 1:

Calculate the gain in mass of the spanner.

Your Answer:

QUESTION 10 -
Lead-acid batteries consist of several cells. A sulphuric acid solution is used as electrolyte in these batteries.

QUESTION 10.1

Marks: 2

Question 1:

Define the term electrolyte.

Your Answer:

QUESTION 10.2

Marks: 2

Attached Section Resource:

03bc1476-bfcc-4d74-bc56-6278cb992e10.png

Question 1:

Write down the half-reaction that takes place at the anode of this cell.

Your Answer:

QUESTION 10.3

Marks: 3

Question 1:

Write down the overall cell reaction when the cell delivers current.

Your Answer:

QUESTION 10.4 -
A number of the cells above are connected in series to form a 300 V battery which operates at standard conditions. Calculate the following:

Marks: 10

Question 1:

Maximum energy stored in the battery if its capacity is 7 500 A∙h

Your Answer:

Question 2:

Minimum number of cells in this battery

Your Answer:

QUESTION 11

QUESTION 11.1 -
A farmer wants to produce the following fruit and vegetables for the market: spinach; potatoes; apples
Write down the NAME of the most important primary nutrient required to enhance:

Marks: 3

Question 1:

Root growth of potato plants

Your Answer:

Question 2:

Leaf growth of spinach

Your Answer:

Question 3:

Flower and fruit production of apple trees

Your Answer:

QUESTION 11.2 -
Ammonia must be produced in large quantities to produce nitrogen-based fertilisers.

Marks: 4

Question 1:

Write down the name of the process used in the industrial preparation of ammonia.

Your Answer:

Question 2:

Write down a balanced chemical equation for the reaction that takes place in the process named above

Your Answer:

QUESTION 11.3

Marks: 2

Question 1:

Ammonium hydrogen phosphate, (NH₄)₂HPO₄, is a type of fertiliser used in agriculture.

Refer to the type of elements of which this fertiliser is composed to give a reason why it will be advantageous for a farmer to use this fertiliser instead of a fertiliser such as ammonium nitrate, NH₄NO₃.

Your Answer:

QUESTION 11.4

Marks: 2

Question 1:

Describe ONE negative impact on humans when fertiliser runs off into dams and rivers as a result of rain.

Your Answer: