Combined Past Paper Questions on Organic Chemistry

15

0620/01/M/J/03 [Turn over

35 The diagram shows how the pH of an industrial waste changes when substance X is added to it.

What is substance X?

A coal

B lime

C salt

D water

36 The diagram shows a model of an organic compound.

What is the name of this compound?

A ethane

B ethanoic acid

C ethanol

D ethene

key

carbon atom

hydrogen atom

7pH

before Xis added

after Xis added

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37 Bitumen is a substance obtained from the fractional distillation of petroleum.

What are the boiling points and the sizes of the molecules in bitumen?

38 Which hydrocarbons in the table are members of the same homologous series?

A 1 and 2

B 1 and 3

C 3 and 4

D 1, 2, 3 and 4

boiling points sizes of molecules

A high large

B high small

C low large

D low small

hydrocarbon 1 2 3 4

state at roomtemperature

gas gas liquid liquid

reaction with oxygen burns burns burns burns

aqueous reaction decolourisesno reaction

decolourisesno reaction

with bromine bromine bromine

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39 Which of the molecules shown can be polymerised?

40 Which conditions are necessary to ferment sugar into ethanol?

H C H

H

H

H C C H

H H

H H

H C C

H

H

O

HO

A

B

C

D

H C C C

H H

H

H

H

yeast temperature/ °C

A absent 30

B absent 70

C present 30

D present 70

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BLANK PAGE

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4 Catalytic cracking is carried out by oil companies to produce high grade petrol. The process is carried out using an aluminium oxide catalyst. The reaction is a type of thermal decomposition.

(a) Explain the meaning of

(i) thermal decomposition.

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

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

(ii) catalyst.

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

..............................................................................................................................[2]

(b) A typical ‘cracking’ reaction is

C10H22 → C8H18 + C2H4

State the name of the unsaturated compound in this equation.

......................................................................................................................................[1]

(c) The table shows some of the products obtained by cracking 100g of different ‘fractions’under the same conditions.

(i) Which ‘fraction’ is the best source of fuel for cars?

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

(ii) Calculate the amount of paraffin ‘fraction’ needed to make 600g of methane.

ForExaminer’s

Use

products obtained / g per 100g of ‘fraction’ cracked

‘fraction’cracked hydrogen methane ethene petrol

ethane 10 5 75 2

paraffin 1 15 30 23

diesel 0 6 20 17

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(iii) Complete the equation for the cracking of ethane to produce hydrogen and ethene.

C2H6 → ……………… + ………………[4]

(d) Ethene can be polymerised to form poly(ethene).

(i) Complete the equation below to show the structure of two units in thepoly(ethene) molecule.

(ii) State the name given to this type of polymerisarion.

...............................................................................................................................[2]

5 A precipitate may be formed when two aqueous solutions are mixed. The colour of theseprecipitates may be used to identify particular aqueous ions.

(a) Complete the following table.

[8]

H

H

C

H

H

C

H

H

C

H

H

C+ →

ForExaminer’s

Use

solution to be added to ion under test test for the ion colour of precipitate

iron(II)

iodide

chloride

sulphate

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(b) Describe the reactions, if any, of zinc and copper(II) ions with an excess of aqueoussodium hydroxide.

(i) zinc ions

addition of aqueous sodium hydroxide .....................................................................

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

excess sodium hydroxide ..........................................................................................

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

(ii) copper(II) ions

addition of aqueous sodium hydroxide .....................................................................

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

excess sodium hydroxide ..........................................................................................

...............................................................................................................................[4]

(c) Each tablet contains the same number of moles of CaCO3 and MgCO3. One tabletreacted with excess hydrochloric acid to produce 0.24 dm3 of carbon dioxide at r.t.p.

CaCO3 + 2HCl → CaCl2 + CO2 + H2OMgCO3 + 2HCl → MgCl2 + CO2 + H2O

(i) Calculate how many moles of CaCO3 there are in one tablet.

number of moles CO2 = ..............

number of moles of CaCO3 and MgCO3 = ..............

number of moles of CaCO3 = ..............[3]

(ii) Calculate the volume of hydrochloric acid, 1.0 mol / dm3, needed to react with onetablet.

number of moles of CaCO3 and MgCO3 in one tablet = ..............Use your answer to (c)(i).

number of moles of HCl needed to react with one tablet = ..............

volume of hydrochloric acid, 1.0 mol / dm3, needed toreact with one tablet = ..............

[2]

ForExaminer’s

Use

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UCLES 2004 0620/01/M/J/04

35 Gas is released in all of the examples below.

fermenting

grapes

acid rain on a

limestone statue

a dog panting

WINE

a candle

burning

Which gas do they all produce?

A carbon dioxide

B hydrogen

C methane

D oxygen

36 What is formed when calcium carbonate is heated?

A calcium and carbon

B calcium and carbon dioxide

C calcium oxide and carbon

D calcium oxide and carbon dioxide

37 Which compound contains three elements?

A ethanol

B ethene

C methane

D poly(ethene)

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38 Four fractions obtained from crude oil (petroleum) are listed below.

Which fraction is paired with a correct use?

fraction use

A bitumen making waxes

B diesel fuel for aircraft

C lubricating making roads

D paraffin fuel for oil stoves

39 The structures of three compounds are shown.

H H

H

H

C

H

HH

H

C CC C C

H

H

CH H

H

H

H

H

H

HH

H

C CC

H

H

C

H

H

C

Why do these substances all belong to the same homologous series?

A They all contain an even number of carbon atoms.

B They all contain the same functional group.

C They are all hydrocarbons.

D They are all saturated.

40 The table shows some suggested reactions involving ethanol.

Which suggestions about the reactants and products are correct?

reaction reactants products

A ethanol and oxygen carbon dioxide and water

B ethene and steam ethanol and hydrogen

C glucose and oxygen ethanol and carbon dioxide

D glucose and water ethanol and oxygen

9

� UCLES 2004 0620/02/M/J/04 [Turn over

For

Examiner’s

Use

4 Organic substances have many uses.

(a) Match the substances in the boxes on the left with the descriptions in the boxes on the

right. The first one has been done for you.

liquid used as a solvent

used for making roads

gas used as a fuel

gas used in making

polymers

methane

ethanol

ethene

bitumen

[3]

(b) Which one of the following would be least likely to be obtained from the fractional

distillation of petroleum? Put a ring around the correct answer.

bitumen ethane ethanol methane [1]

10

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(c) Some reactions of organic compounds are shown below.

A n CH2=CH2

B C3H8 + 5O2

C C6H12O6

glucose

D

( CH2 CH2 ) n

3CO2 + 4H2O

2CO2 + 2C2H5OH

C6H14 + C2H4C8H18

(i) Which one of the reactions, A, B, C or D, shows fermentation?

(ii) Which one of the reactions, A, B, C or D, shows polymerization?

(iii) Which one of the reactions, A, B, C or D, shows combustion?

(iv) Which one of the reactions, A, B, C or D, shows cracking?

[4]

(d) The hydrocarbon C8H

18is an alkane.

(i) What is meant by the term hydrocarbon?

(ii) Explain why this hydrocarbon is an alkane.

[2]

9

UCLES 2004 0620/03/M/J/04 [Turn over

For

Examiner’s

Use

6 In 2002, Swedish scientists found high levels of acrylamide in starchy foods that had been

cooked above 120o

C. Acrylamide, which is thought to be a risk to human health, has the

following structure.

C C

H

H

H

CONH2

(a) (i) It readily polymerises to polyacrylamide. Draw the structure of this polymer.

[2]

(ii) Starch is formed by polymerisation. It has a structure of the type shown below.

Name the monomer.

O

O[1]

(iii) What are the differences between these two polymerisation reactions, one forming

polyacrylamide and the other starch?

[2]

(b) Acrylamide hydrolyses to form acrylic acid and ammonium ions.

(i) Describe the test for the ammonium ion.

test

result [2]

(ii) Given an aqueous solution, concentration 0.1 mol / dm3

, how could you show that

acrylic acid is a weak acid.

[2]

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(c) The structural formula of acrylic acid is shown below. It forms compounds called

acrylates.

C C

H

H

COOH

H

(i) Acrylic acid reacts with ethanol to form the following compound.

C C

H

H

COOCH2CH3

H

Deduce the name of this compound. What type of organic compound is it?

name

type of compound [2]

(ii) Acrylic acid is an unsaturated compound. It will react with bromine. Describe the

colour change and draw the structural formula of the product of this addition

reaction.

colour change

structural formula of product

[2]

13

© UCLES 2005 0620/01/M/J/05 [Turn over

34 The presence of nitrates in soil can be shown by warming the soil with aqueous sodium hydroxide and aluminium foil.

Which gas is given off?

A ammonia

B carbon dioxide

C nitrogen

D nitrogen dioxide 35 Dolomite is a rock that contains magnesium carbonate.

A piece of dolomite is heated strongly in air.

Which word equation correctly describes the reaction that takes place?

A magnesium carbonate + water → magnesium hydroxide + carbon dioxide

B magnesium carbonate + oxygen → magnesium oxide + carbon dioxide + water

C magnesium carbonate + oxygen → magnesium oxide + water

D magnesium carbonate → magnesium oxide + carbon dioxide 36 Which two compounds have molecules in which there is a double bond?

A ethane and ethanoic acid

B ethane and ethanol

C ethene and ethanoic acid

D ethene and ethanol 37 Which substance is found in crude oil?

A bitumen

B ethanol

C ethanoic acid

D poly(ethene)

14

© UCLES 2005 0620/01/M/J/05

38 Which statement about a family of organic compounds describes an homologous series?

All compounds in the family have the same

A functional group.

B physical properties.

C relative molecular mass.

D structural formula. 39 Which column describes ethane and which column describes ethene?

hydrocarbon

1 2 3 4

state at room temperature gas gas liquid liquid

reaction with oxygen burns burns burns burns

reaction with

aqueous bromine no reaction

decolourises

bromine no reaction

decolourises

bromine

A 1 (ethane) and 2 (ethene)

B 1 (ethane) and 3 (ethene)

C 2 (ethene) and 3 (ethane)

D 3 (ethane) and 4 (ethene) 40 Which of the products C12H24 and H2 could be formed by cracking dodecane, C12H26?

C12H24 H2

A � �

B � �

C � �

D � �

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4 Poly(ethene) is a plastic which is made by polymerizing ethene, C2H4. (a) Which one of the following best describes the ethene molecules in this reaction? Put a ring around the correct answer.

alcohols alkanes monomers polymers products [1]

(b) The structure of ethane is shown below.

CH

H

C

H

HH

H

Explain, by referring to its bonding, why ethane cannot be polymerized.

[1]

(c) Draw the structure of ethene, showing all atoms and bonds. [1] (d) Ethene is obtained by cracking alkanes. (i) Explain the meaning of the term cracking.

[1]

(ii) What condition is needed to crack alkanes?

[1]

(iii) Complete the equation for cracking decane, C10H22.

C10H22 C2H4 + ................. [1]

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(e) Some oil companies ‘crack’ the ethane produced when petroleum is distilled. (i) Complete the equation for this reaction.

C2H6 C2H4 + ................. [1]

(ii) Describe the process of fractional distillation which is used to separate the different

fractions in petroleum.

[2]

(iii) State a use for the following petroleum fractions.

petrol fraction

lubricating fraction [2]

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For

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3 A South Korean chemist has discovered a cure for smelly socks. Small particles of silver are attached to a polymer, poly(propene), and this is woven into the socks.

(a) (i) Give the structural formula of the monomer. [1] (ii) Draw the structural formula of the polymer. [2] (iii) Suggest which one, monomer or polymer, will react with aqueous bromine and why?

[2]

(b) To show that the polymer contains silver the following test was carried out. The polymer fibres were chopped into small pieces and warmed with nitric acid. The

silver atoms were oxidised to silver(I) ions. The mixture was filtered. Aqueous sodium chloride was added to the filtrate and a white precipitate formed.

(i) Why was the mixture filtered?

[1]

(ii) Explain why the change of silver atoms to silver ions is oxidation.

[1]

(iii) Give the name of the white precipitate.

[1]

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(c) The unpleasant smell is caused by carboxylic acids. Bacteria cause the fats on the skin to be hydrolysed to these acids. Silver kills the bacteria and prevents the hydrolysis of the fats.

(i) Fats are esters. Give the name and structural formula of an ester.

name [1]

structural formula [1] (ii) Complete the word equation.

Ester + water carboxylic acid + [1]

(d) Propanoic acid is a weak acid. (i) The following equation represents its reaction with ammonia.

CH3 CH2 COOH + NH3 CH3 CH2 COO– + NH4

+

Explain why propanoic acid behaves as an acid and ammonia as a base.

[3]

(ii) Explain the expression weak acid.

[1]

14

© UCLES 2006 0620/01/M/J/06

34 The diagram shows the pH values of the soil in X and Y, two parts of the garden of a house.

pH 7.0

XpH 5.5

Y

The house owner wishes to use lime to neutralise the soil in one part of the garden.

To which part should the lime be added, and why?

part of garden because lime is

A X acidic

B X basic

C Y acidic

D Y basic

35 In the molecule shown, the two –OH groups are numbered.

H

CO

O

O

H

H

H

C

H

H

H

C

H

C

12

Which of these –OH groups react with aqueous sodium hydroxide?

1 2

A � �

B � �

C � �

D � �

15


36 When a suitable catalyst is used, ethene reacts with steam.

What is the structure of the compound formed?

O

O

H

OO

OO

HH

C C

H

CH

H

H

C

H

O H

A

H

COH

H

H

C

H

O H

B

H

CH

H

C

C D

37 The diagram shows the separation of crude oil into fractions.

petrol

X

Y

Z

bitumen

crude oil

What could X, Y and Z represent?

X Y Z

A diesel lubricating oil paraffin

B lubricating oil diesel paraffin

C lubricating oil paraffin diesel

D paraffin diesel lubricating oil

16

© UCLES 2006 0620/01/M/J/06

38 Which of the compounds shown are used as fuels?

H

CH

H

H

C

H

O H

H

CH

H

H

C

H

H

O

O

H

H

CH

H

C

1 2 3

1 2 3

A � � �

B � � �

C � � �

D � � �

39 Which set of diagrams shows three substances that are all in the same homologous series?

A

B

C

D

H H

H H

H H

C C H HC C

H H

H

H

C

H

H

CH O H H C

O

O

H

H

H

H C C

H

H

C

H

H

CC

O

H

H

H

O

H

C C

H

H

C

H

H

H

H

H

C

H

HC

H

H C C

H

H H

H

O

H

H

H C C

H

H

C C

H

H H

C C

H

H

H

H

C C

H

H

H

H

17


40 The diagram shows the structure of a small molecule.

CH3

H

H

H

C C

Which chain-like molecule is formed when these small molecules link together?

C C C C

CH3

CH3

CH3

CH3

H

H H

H

A

C C C C

CH3

H

CH3H

H H H

H

B

C C C C

CH3

CH3

CH3

CH3CH3 CH3

CH3 CH3

C

C C C C

CH3

CH3

CH3

CH3

H

H H

H

D

8

© UCLES 2006 0620/02/M/J//06

For

Examiner's

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4 Coal gas is made by heating coal in the absence of air. The table shows the composition of coal gas.

name of gas % of gas in coal gas

hydrogen 50

methane 30

carbon monoxide 7

carbon dioxide 4

nitrogen 4

ethene 3

oxygen 2

(a) (i) Which element in this table is a highly flammable gas?

[1]

(ii) Which compound in the table is an alkene?

[1]

(iii) Which compound in the table turns limewater milky?

[1]

(b) Describe a test you can use to distinguish between ethene and methane.

test

result with ethene

result with methane [3]

9

© UCLES 2006 0620/02/M/J//06 [Turn Over

For

Examiner's

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(c) Molecules of ethene can react with each other to make poly(ethene). (i) What is the name given to this type of reaction?

[1]

(ii) Which formula below best represents a molecule of poly(ethene)? Tick one box.

C C

H

H

H

H

n

C C

H

H

H

CH3

n

C C

H H

n

C C

H

H

H

H

[1] (d) Ethene can be manufactured by breaking down hydrocarbons into smaller molecules

using high temperatures and a catalyst. State the name given to this type of reaction.

[1]

(e) A liquid is also formed when coal is heated in the absence of air. This liquid contains a high percentage of ammonia. (i) Describe a test for ammonia.

test

result [2]

(ii) Ammonia has the formula NH3. Calculate the relative molecular mass of ammonia. [1] (f) Coal contains a small amount of sulphur. Explain why burning coal is harmful to the environment.

[2]

14

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7 The fractional distillation of crude oil usually produces large quantities of the heavier fractions. The market demand is for the lighter fractions and for the more reactive alkenes. The heavier fractions are cracked to form smaller alkanes and alkenes as in the following example.

C8H18 C4H10 + C4H8

octane

butane

butenes

(a) (i) Write a different equation for the cracking of octane.

C8H18 + [1]

(ii) The cracking of octane can produce isomers with the molecular formula C4H8.

Draw the structural formulae of two of these isomers. [2] (b) (i) Give the essential condition for the reaction between chlorine and butane.

[1]

(ii) What type of reaction is this?

[1]

(iii) This reaction produces a mixture of products. Give the names of two products

that contain four carbon atoms per molecule.

and [2]

15

Permission to reproduce items where third-party owned material protected by copyright is included has been sought and cleared where possible. Every reasonable effort has been made by the publisher (UCLES) to trace copyright holders, but if any items requiring clearance have unwittingly been included, the publisher will be pleased to make amends at the earliest possible opportunity.

University of Cambridge International Examinations is part of the University of Cambridge Local Examinations Syndicate (UCLES), which is itself a department of the University of Cambridge.

© UCLES 2006 0620/03/M/J/06

For

Examiner's

Use

(c) Alkenes are more reactive than alkanes and are used to make a range of organic chemicals. Propene, CH3–CH=CH2, is made by cracking. Give the structural formula of the addition product when propene reacts with the following.

(i) water [1] (ii) bromine [1] (d) Propene reacts with hydrogen iodide to form 2 - iodopropane.

CH3−CH=CH2 + HI CH3−CHI−CH3

1.4 g of propene produced 4.0 g of 2 - iodopropane. Calculate the percentage yield.

moles of CH3–CH=CH2 reacted =

maximum moles of CH3–CHI–CH3 that could be formed =

mass of one mole of CH3–CHI–CH3 = 170 g

maximum mass of 2 - iodopropane that could be formed =

percentage yield % [4]

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© UCLES 2007 0620/01/M/J/07

36 When limestone is heated very strongly in air, lime is made.

What is the formula of limestone and of lime?

limestone lime

A CaCO3 CaO

B CaCO3 Ca(OH)2

C CaO CaCO3

D Ca(OH)2 CaCO3

37 Bromine and steam each react with ethene.

Which of these reactions need a catalyst?

Br2 / ethene steam / ethene

A � �

B � �

C � �

D � �

38 What are formed when glucose is fermented?

A ethanol and carbon dioxide

B ethanol and oxygen

C ethene and carbon dioxide

D ethene and oxygen 39 Which formula represents a compound that dissolves in water to form an acidic solution?

A

H

H

H

C

H

H

C

H

H

C H

C

H

H

H

C

H

H

C

H

H

C

H

H

C O H

D

H

H

H

C

H

H

C C

O

O

H

B

H

H

H

C

H

C

H

H

C

15

Permission to reproduce items where third-party owned material protected by copyright is included has been sought and cleared where possible. Every reasonable effort has been made by the publisher (UCLES) to trace copyright holders, but if any items requiring clearance have unwittingly been included, the publisher will be pleased to make amends at the earliest possible opportunity.

© UCLES 2007 0620/01/M/J/07

40 Butane reacts as shown.

butane butene + hydrogencatalyst

and heat

What is this type of reaction?

A combustion

B cracking

C polymerisation

D reduction

7


For

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3 Hydrogen is a fuel which can be obtained from water by electrolysis. Petrol is a fuel obtained by the fractional distillation of petroleum. (a) (i) Complete the equation for the burning of hydrogen.

H2 + O2 → H2O [1]

(ii) Suggest why hydrogen is a renewable source of energy.

[1]

(iii) When hydrogen is burnt, heat is given off. State the name of the type of reaction

which gives off heat.

[1]

(b) Petrol is a mixture of alkanes. One of the alkanes in petrol is octane, C8H18. What products are formed when octane is completely burnt in air?

[2]

(c) Petrol is only one of the fractions obtained from the fractional distillation of petroleum. State the name of two other fractions obtained from the distillation of petroleum. Give a

use for each of these fractions.

fraction

use

fraction

use [4]

8

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(d) More petrol can be made by cracking less useful petroleum fractions. (i) What do you understand by the term cracking?

[1]

(ii) State two conditions needed for cracking.

[2]

(iii) Alkenes can be formed by cracking. The simplest alkene is ethene. Draw a diagram to show the structure of ethene. Show all atoms and bonds. [1] [Total: 13]

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7 Esters, fats and polyesters all contain the ester linkage. (a) The structural formula of an ester is given below.

C

H

H

H

H

CCO

O

H

H

H

H

C H

H

H

H

C C

Name two chemicals that could be used to make this ester and draw their structural

formulae. Show all bonds.

names and [2]

structural formulae [2] (b) (i) Draw the structural formula of a polyester such as Terylene. [2] (ii) Suggest a use for this polymer.

[1]

12

© UCLES 2007 0620/03/M/J/07

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(c) Cooking products, fats and vegetable oils, are mixtures of saturated and unsaturated esters.

The degree of unsaturation can be estimated by the following experiment. 4 drops of

the oil are dissolved in 5 cm3 of ethanol. Dilute bromine water is added a drop at a time until the brown colour no longer disappears. Enough bromine has been added to the sample to react with all the double bonds.

cooking product

mass of saturated fat in 100 g of product / g

mass of unsaturated fat in 100 g of product / g

number of drops of bromine water

margarine 35 35 5

butter 45 28 4

corn oil 10 84 12

soya oil 15 70 10

lard 38 56

(i) Complete the one blank space in the table. [1] (ii) Complete the equation for bromine reacting with a double bond.

C C + Br2 [2] (iii) Using saturated fats in the diet is thought to be a major cause of heart disease.

Which of the products is the least likely to cause heart disease?

[1]

13

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(d) A better way of measuring the degree of unsaturation is to find the iodine number of the unsaturated compound. This is the mass of iodine that reacts with all the double bonds in 100 g of the fat.

Use the following information to calculate the number of double bonds in one molecule

of the fat. Mass of one mole of the fat is 884 g.

One mole of I2 reacts with one mole C C.

The iodine number of the fat is 86.2 g. Complete the following calculation.

100 g of fat reacts with 86.2 g of iodine.

884 g of fat reacts with g of iodine.

One mole of fat reacts with moles of iodine molecules.

Number of double bonds in one molecule of fat is [3]

[Total:14]

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© UCLES 2008 0620/01/M/J/08

37 Cholesterol occurs naturally in the body.

Its name indicates that it has the same functional group as

A

H

H

H

C

H

H

C H

B

H

H

H

C

H

H

C O H

C

H

H

C

H

H

C

D

H

H

H

C C

H

O

O

38 Which fuel is a mixture of hydrocarbons?

A coal

B methane

C petroleum

D wood 39 In the diagram, which substance could be ethene?

State at room temperature

Is it saturated? Is it saturated?

gas liquid

A B

yes no

C D

yes no

40 Which properties do butane, propene and ethanol all have?

burn polymerise

A � �

B � �

C � �

D � �

12

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Examiner's

Use

6 Petroleum is separated into useful fractions by distillation.

petroleum

fuel gas

fractions

petrol

paraffin

diesel

lubricating fraction

bitumen (a) (i) What do you understand by the term fraction?

[1]

(ii) Which fraction has the lowest boiling point?

[1]

(iii) Describe how distillation is used to separate these fractions.

[2]

(iv) State a use for

the paraffin fraction,

the bitumen fraction. [2]

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(b) Ethene can be made by cracking certain hydrocarbon fractions. (i) Explain what is meant by the term cracking.

[1]

(ii) Complete the equation for the cracking of tetradecane, C14H30.

C14H30 + C2H4 [1]

(c) Ethanol is formed when steam reacts with ethene at high pressure and temperature. A

catalyst of phosphoric acid is used.

ethene + steam ethanol (i) What is the function of the catalyst?

[1]

(ii) What is the meaning of the symbol ?

[1]

(iii) Ethanol is also formed when yeast grows in sugar solution. What is this process called? Put a ring around the correct answer.

addition combustion fermentation neutralisation

[1]

(iv) Phosphoric acid is a typical acid. State what you would observe when a solution of

phosphoric acid is added to

blue litmus,

a solution of sodium carbonate. [2]

[Total: 13]

8

© UCLES 2008 0620/31/M/J/08

For

Examiner's

Use

(c) The fermentation of glucose is catalysed by enzymes from yeast. Yeast is added to aqueous glucose, the solution starts to bubble and becomes cloudy as more yeast cells are formed.

C6H12O6(aq) 2C2H5OH(aq) + 2CO2(g)

The reaction is exothermic. Eventually the fermentation stops when the concentration of ethanol is about 12%. (i) What is an enzyme?

[1]

(ii) Pasteur said that fermentation was respiration in the absence of air. Suggest a

definition of respiration.

[2]

(iii) On a large scale, the reaction mixture is cooled. Suggest a reason why this is

necessary.

[1]

(iv) Why does the fermentation stop? Suggest two reasons.

[2]

(v) When the fermentation stops, there is a mixture of dilute aqueous ethanol and

yeast. Suggest a technique which could be used to remove the cloudiness due to the yeast.

[1]

Name a technique which will separate the ethanol from the ethanol / water mixture.

[1]

[Total: 14]

13


35 The diagram shows stages in the purification of water.

Which stage uses chlorine?

water at pH9

+ bacteria

+ large solids

+ fine solids

water at pH9

+ bacteria

+ fine solids

water at pH9

+ bacteria

water at pH7

+ bacteria

pure water

at pH7

A B

C

D

36 Which element is not added to a fertiliser?

A aluminium

B nitrogen

C phosphorus

D potassium 37 A compound has the formula CH

3

CH2

CH=CH2

.

Which row in the table shows the type of compound and the colour change when aqueous bromine is added?

type of compound colour change

A saturated brown to colourless

B saturated colourless to brown

C unsaturated brown to colourless

D unsaturated colourless to brown

14

© UCLES 2009 0620/11/M/J/09

38 The diagram shows an industrial process. Substance M is one of the substances produced by this process and is used as aircraft fuel.

substance M

What is this process and what is substance M?

process substance M

A fractional distillation paraffin

B fractional distillation petrol

C thermal decomposition paraffin

D thermal decomposition petrol


H H

H

H

C

H

HH

H

C CC C C

H

H

CH H

H

H

H

H

H

HH

H

C CC

H

H

C

H

H

C

Why do these substances all belong to the same homologous series?

A They all contain an even number of carbon atoms.


C They are all hydrocarbons.

D They are all saturated. 40 Which bond is not in a molecule of ethanoic acid?

A C–O B C=O C C=C D O–H

7


For

Examiner's

Use

3 Petroleum is a mixture of hydrocarbons which can be separated into fractions such as petrol, paraffin and diesel.

(a) State the name of the process used to separate these fractions.

[1]

(b) Name two other fractions which are obtained from petroleum .

and [2]

(c) Give one use for the paraffin fraction.

[1]

(d) Many of the compounds obtained from petroleum are alkanes. Which two of the following structures are alkanes?

C

A B

H

H

HH C

C

H

H

OH H C

D

H

H

CH C H

H

H

H

H

C C

H

H

H

H

[1]

(e) Use words from the list below to complete the following sentence.

ethane ethene hydrogen nitrogen oxygen

reactive unreactive water

Alkanes such as are generally but they can

be burnt in to form carbon dioxide and [4]

(f) Alkanes are saturated hydrocarbons. What do you understand by the terms

(i) saturated,

(ii) hydrocarbon?

[2]

[Total: 11]

12

© UCLES 2009 0620/31/M/J/09

For

Examiner's

Use

8 Lactic acid can be made from corn starch.

CH3 CH COOH

OH

lactic acid It polymerises to form the polymer, polylactic acid (PLA ) which is biodegradable. (a) Suggest two advantages that PLA has compared with a polymer made from petroleum.

[2]

(b) The structure of PLA is given below.

CH3 O

CHO C

CH3

O CH

(i) What type of compound contains the group that is circled?

[1]

(ii) Complete the following sentence.

Lactic acid molecules can form this group because they contain both an

group and an group. [2]

(iii) Is the formation of PLA, an addition or condensation polymerisation? Give a

reason for your choice.

[2]

13


For

Examiner's

Use

(c) When lactic acid is heated, acrylic acid is formed.

C C COOH

OH

H

H

H

H

lactic acid acrylic acid

C C

H

H

H

COOH

(i) Complete the word equation for the action of heat on lactic acid.

lactic acid → + [1]

(ii) Describe a test that would distinguish between lactic acid and acrylic acid.

test

result for lactic acid

result for acrylic acid [3]

(iii) Describe a test, other than using an indicator, which would show that both

chemicals contain an acid group.

test

result

[2]

[Total: 13]

13


35 To grow roses, a fertiliser containing nitrogen, phosphorus and potassium is needed.

For the best flowers, the fertiliser should contain a high proportion of potassium.

Which fertiliser is best for roses?

proportion by mass fertiliser

N P K

A 9 0 25

B 13 13 20

C 29 5 0

D 29 15 5

36 The diagram shows three types of item.

cutlery cooking paninstruments used

in hospitals

Which method of rust prevention can be used for all three types of item?

A coating with plastic

B covering with grease

C galvanising

D using stainless steel 37 Which structure is incorrect?

H

H H

H H

HC C

CA

H

H H

H H

HC C

B

H

H O

H

OC C H

D

H

H H

H

OC C

H

H

14

© UCLES 2010 0620/11/M/J/10

38 Which structure shows a compound that belongs to a different homologous series to propane?

A B C D

C C

H

H

H

H

H C

H

H

H H C

H

H

HC C C

H

H

H

H

H

H

H C

H

H

HC C C

H

H

H

H

H

H

HH

H 39 A macromolecule is a very large molecule.

Macromolecules can be made by joining smaller molecules together. This is called polymerisation.

Which row in the table describes the formation of a polymer?

monomer polymer

A ethane poly(ethane)

B ethene poly(ethene)

C ethane poly(ethene)

D ethene poly(ethane)

40 Diesel, petrol and bitumen are all

A fuels.

B hydrocarbons.

C lubricants.

D waxes.

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7 Petroleum is a mixture of hydrocarbons. Two of the processes carried out in an oil refi nery are fractional distillation of petroleum and

cracking of hydrocarbon fractions.

(a) Which property of hydrocarbons is used to separate petroleum into fractions? Tick one box.

boiling point

chemical reactivity

electrical conductivity

melting point[1]

(b) Match the fractions on the left with their uses on the right. The fi rst one has been done for you.

fuel for home heating

making roads

waxes and polishes

making chemicals

jet fuel

bitumen

fuel oil

kerosene


naphtha

[4]

13

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ForExaminer’s

Use

(c) Cracking is used to break down long chained alkanes into shorter chained alkanes and alkenes.

(i) State two conditions needed for cracking.

1. ................................................................................................................................

2. .......................................................................................................................... [2]

(ii) The hydrocarbon, C14H30, can be cracked to make ethene and one other hydrocarbon.

Complete the equation for this reaction.

C14H30 → C2H4 + ...............[1]

(iii) Draw the full structure of ethene showing all atoms and bonds.

[1]

(d) State the name of the polymer formed from ethene.

..................................................................................................................................... [1]

(e) Ethene is used to make ethanol.

(i) Which substance is needed for this reaction? Put a ring around the correct answer.

ammonia hydrogen oxygen steam[1]

(ii) Phosphoric acid is a catalyst in this reaction. What do you understand by the term catalyst?

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

.............................................................................................................................. [1]

[Total: 12]

6

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Use

(ii) What is the meaning of the symbol (II) in iron(II)? Tick one box.

the number of outer shell electrons

the difference between the neutron and proton number

the oxidation state

the type of isotope

[1]

(iii) Tannins are polymers. What do you understand by the term polymer?

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

.............................................................................................................................. [2]

(d) One of the carboxylic acids present in ink is gallic acid. The structure of gallic acid is shown below.

HO OH

OH

OHO

C

(i) On the structure above, put a ring around the carboxylic acid functional group. [1]

(ii) Gallic acid is a good reducing agent. What do you understand by the term reduction?

.............................................................................................................................. [1]

[Total: 9]

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ForExaminer’s

Use

(d) The structure of some organic compounds found in plant leaves are shown below.

C C

H

H

H

H

C C

OH

H

H

O H

C C

H

H

H C

O

O H

H

H

A B C

C C

H

H

H O

H

H

H

D

(i) Which one of these compounds is an unsaturated hydrocarbon?

............................................................................................................................. [1]

(ii) Describe a chemical test for an unsaturated hydrocarbon.

test .............................................................................................................................

result .................................................................................................................... [2]

(iii) What do you understand by the term hydrocarbon?

.............................................................................................................................. [1]

(iv) State the name of compound B.

.............................................................................................................................. [1]

(v) To which homologous series does compound D belong?

............................................................................................................................. [1]

[Total: 12]

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(e) Coal is a fuel containing carbon. When coal is burnt, carbon dioxide is produced. Explain how the increase in carbon dioxide concentration in the atmopshere affects the

world’s climate.

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

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

..................................................................................................................................... [2]

(f) Coal also contains small amounts of sulfur. Explain how burning coal leads to acid rain.

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

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

..................................................................................................................................... [2]

(g) Methane is a fuel.

(i) Which one of the following is a natural source of methane? Tick one box.

waste gases from respiration in plants

waste gases from digestion in animals

gases from photosynthesis in plants

gases from forest fi res

[1]

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(ii) Draw a diagram to show the arrangement of the electrons in a molecule of methane, CH4.

Use ● for an electron from a carbon atom × for an electron from a hydrogen atom

[1]

(iii) Methane belongs to the alkane homologous series. Name one other alkane.

.............................................................................................................................. [1]

[Total: 13]

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4 Hydrolysis is used in chemistry to break down complex molecules into simpler ones.

(a) Compounds containing the group are esters.

(i) Give the names and formulae of the two compounds formed when the ester ethyl propanoate is hydrolysed.

CH2

C

O

O

CH3

CH2

CH3

name ...................................................... name ......................................................

formula formula

[4]

(ii) Fats are naturally occurring esters. They can be hydrolysed by boiling with aqueous sodium hydroxide.

C17

H35

COOCH2

C17

H35

COOCH2

C17

H35

COOCH + 3NaOH → 3C17

H35

COONa + CHOH

CH2OH

fat

CH2OH

What type of compound has the formula C17H35COONa and what is its main use?

type of compound ................................................................................................ [1]

use ....................................................................................................................... [1]

(iii) Name a synthetic polyester.

.............................................................................................................................. [1]

C or

O

O

COO

7


ForExaminer’s

Use

(b) The structure of a typical protein is drawn below.

N C

OH H

N C

O H

N C

O OH

N C

(i) What is the name of the polymer linkage?

.............................................................................................................................. [1]

(ii) Draw the structural formula of a man-made polymer with the same linkage.

[3]

(iii) A protein can be hydrolysed to a mixture of amino acids which are colourless. Individual amino acids can be identifi ed by chromatography. The Rf value of the amino acid glycine is 0.5. Describe how you could show that glycine was present on a chromatogram.

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

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

.............................................................................................................................. [3]

[Total: 14]

5 Carbon and silicon are elements in Group IV. Both elements have macromolecular structures.

(a) Diamond and graphite are two forms of the element carbon.

(i) Explain why diamond is a very hard substance.

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

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

.............................................................................................................................. [2]

(ii) Give one use of diamond.

.............................................................................................................................. [1]

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ForExaminer’s

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(i) What type of reaction is reaction 1? .................................................................... [1]

(ii) Deduce the name of the colourless gas mentioned in reaction 1.

.............................................................................................................................. [1]

(iii) What is the name of the iron compound formed in reaction 2?

.............................................................................................................................. [1]

(iv) Balance the equation for reaction 3.

..........Fe(OH)2 + O2 + ..........H2O → ..........Fe(OH)3[1]

(v) Explain why the change Fe(OH)2 to Fe(OH)3 is oxidation.

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

.............................................................................................................................. [1]

(vi) Explain why iron in electrical contact with a piece of zinc does not rust.

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

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

.............................................................................................................................. [3]

[Total: 13]

4 But-1-ene is a typical alkene. It has the structural formula shown below.

CH3

CH2

CH2

CH

The structural formula of cyclobutane is given below.

C

C

C

C

H

H

H

HH

H

H

H

(a) These two hydrocarbons are isomers.

(i) Defi ne the term isomer.

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

.............................................................................................................................. [2]

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(ii) Draw the structural formula of another isomer of but-1-ene.

[1]

(iii) Describe a test which would distinguish between but-1-ene and cyclobutane.

reagent ......................................................................................................................

result with but-1-ene ..................................................................................................

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

result with cyclobutane ..............................................................................................

.............................................................................................................................. [3]

(b) Describe how alkenes, such as but-1-ene, can be made from alkanes.

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

..................................................................................................................................... [2]

(c) Name the product formed when but-1-ene reacts with:

bromine, ...................................................................................................................... [1]

hydrogen, .................................................................................................................... [1]

steam. ......................................................................................................................... [1]

[Total: 11]

14

© UCLES 2011 0620/11/M/J/11

36 Compounds containing five carbon atoms in a molecule may have names beginning with ‘pent…’.

What is the name of the compound shown?

key

= carbon

= oxygen

= hydrogen

A pentane

B pentanoic acid

C pentanol

D pentene 37 Which industrial process is shown in the diagram?

crudeoil vapour

bitumen

wastegases

petrol

paraffin

diesel

lubricatingoils

A cracking

B fermentation

C fractional distillation

D polymerisation

15

© UCLES 2011 0620/11/M/J/11

38 The diagram shows the structures of three compounds.

O

CH H

OH

CH HC

H

H

H

H

O

C C

H

H

C H

Why do these three compounds belong to the same homologous series?

A They all contain carbon, hydrogen and oxygen.


C They are all carbon based molecules.

D They are all flammable liquids. 39 What is the main constituent of natural gas?

A carbon dioxide

B ethane

C hydrogen

D methane 40 What is not essential for the formation of ethanol by fermentation?

A light

B sugar

C yeast

D water

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Use

4 The structures of some organic compounds are shown below.

n

C

H

H

C

H

H

D

CH

H

H

C C

H

H

H

H

H

A

CH

H

H

C O H

H

H

E

CH

H

Br Br

C H

H

C

C

H

H

C C

H

H

H

H

B

(a) Which one of these structures represents

(i) a polymer,

(ii) an unsaturated hydrocarbon,

(iii) the product of the catalytic addition of steam to ethene,

(iv) a product of the addition of aqueous bromine to ethene?[4]

(b) (i) Balance the equation for the complete combustion of compound A, C3H8.

C3H8 + ............O2 → 3CO2 + ............H2O

[2]

(ii) State the name of two substances formed when compound A undergoes incomplete combustion.

......................................................... and ......................................................... [2]

(c) Complete the structure of ethanoic acid to show all atoms and bonds.

CH

H

H

[1]

[Total: 9]

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4 Ethanol can be produced by fermentation or by the catalytic addition of steam to ethene.

(a) (i) Complete the word equation for fermentation.

glucose → ............................................... + ethanol[1]

(ii) State the conditions needed for fermentation.

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

.............................................................................................................................. [2]

(b) (i) Complete the equation for the catalytic addition of steam to ethene by drawing the structures of water and ethanol in the boxes.

C

H

H

C

H

H

C2H

4C

2H

5OHH

2O+ →

+ →

[2]

(ii) Ethene is an unsaturated hydrocarbon. Describe a test for an unsaturated hydrocarbon.

test .............................................................................................................................

result .................................................................................................................... [2]

(c) Ethanol can be used as a fuel. State the names of the products formed when ethanol undergoes complete

combustion.

......................................................... and ......................................................... [2]

(d) Complete these sentences using words from the list.

different functional homologous similar unreactive unsaturated

Ethanol is a member of the alcohol ............................... series.

All alcohols have .......................... chemical properties because they contain the same

.......................... group. [3]

[Total: 12]

6

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(d) 20.0 cm3 of aqueous sodium hydroxide, 2.00 mol / dm3, was placed in a beaker. The temperature of the alkali was measured and 1.0 cm3 portions of hydriodic acid were added. After each addition, the temperature of the mixture was measured. Typical results are shown on the graph.

temperature

volume of

acid added18.0 cm3

NaOH(aq) + HI(aq) → NaI(aq) + H2O(l)

(i) Explain why the temperature increases rapidly at fi rst then stops increasing.

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

.............................................................................................................................. [2]

(ii) Suggest why the temperature drops after the addition of 18.0 cm3 of acid.

.............................................................................................................................. [1]

(iii) In another experiment, it was shown that 15.0 cm3 of the acid neutralised 20.0 cm3 of aqueous sodium hydroxide, 1.00 mol / dm3. Calculate the concentration of the acid.

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

.............................................................................................................................. [2]

[Total: 12]

6 The structural formula of a butanol is given below.

CH3 — CH2 — CH2 — CH2 — OH

(a) Butanol can be made from petroleum and also by fermentation.

(i) Describe the chemistry of making butanol from petroleum by the following route.

petroleum → butene → butanol

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

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

.............................................................................................................................. [3]

7


ForExaminer’s

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(ii) Explain, in general terms, what is meant by fermentation.

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

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

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

.............................................................................................................................. [3]

(b) Butanol can be oxidised to a carboxylic acid by heating with acidifi ed potassium manganate(VII). Give the name and structural formula of the carboxylic acid.

name ........................................................................................................................... [1]

structural formula

[1]

(c) Butanol reacts with ethanoic acid to form a liquid, X, which has the sweet smell of bananas. Its empirical formula is C3H6O and its Mr is 116.

(i) What type of compound is liquid X?

.............................................................................................................................. [1]

(ii) Give the molecular formula of liquid X.

.............................................................................................................................. [1]

(iii) Draw the structural formula of X. Show all the individual bonds.

[2]

[Total: 12]

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8 There are two types of polymerisation - addition and condensation.

(a) Explain the difference between them.

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

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

..................................................................................................................................... [2]

(b) Poly(dichloroethene) is used to package food. Draw its structure. The structural formula of dichloroethene is shown below.

C C

Cl

Cl

H

H

[2]

(c) The polymer known as PVA is used in paints and adhesives. Its structural formula is shown below.

CH2

CH

OOCCH3

OOCCH3

CH2

CH

Deduce the structural formula of its monomer.

[1]

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(d) A condensation polymer can be made from the following monomers.

HOOC(CH2)4COOH and H2N(CH2)6NH2

Draw the structural formula of this polymer.

[3]

[Total: 8]

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6 (a) Methanol can be made from a mixture of carbon monoxide and hydrogen.

CO(g) + 2H2(g) CH3OH(g)

The forward reaction is exothermic.

(i) Explain why the concentration of methanol at equilibrium does not change.

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

.............................................................................................................................. [2]

(ii) Suggest conditions, in terms of temperature and pressure, which would give a high yield of methanol.

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

.............................................................................................................................. [2]

(iii) How would the conditions used in practice compare with those given in (ii)? Give an explanation of any differences.

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

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

.............................................................................................................................. [2]

(b) Biodiesel is made from a vegetable oil by the following reaction.

+ +3CH3OH → 3C

17H

35COOCH

3

CH2OH

CHOH

CH2OH

C17

H35

CO2

CH2

C17

H35

CO2

CH

C17

H35

CO2

CH2

vegetable oil methanol biodiesel glycerol

(i) What type of compound are vegetable oil and biodiesel?

.............................................................................................................................. [1]

(ii) What other useful product is made from vegetable oil by heating it with aqueous sodium hydroxide?

.............................................................................................................................. [1]

(iii) Suggest an explanation why making and using biodiesel has a smaller effect on the percentage of carbon dioxide in the atmosphere than using petroleum-based diesel.

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

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

.............................................................................................................................. [2]

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(c) Petroleum-based diesel is a mixture of hydrocarbons, such as octane and octene.

(i) ‘Oct’ means eight carbon atoms per molecule. Draw a structural formula of an octene molecule.

[1]

(ii) Describe a test which would distinguish between octane and octene.

test .............................................................................................................................

result with octane .......................................................................................................

result with octene ................................................................................................. [3]

[Total: 14]

7 Chlorine reacts with phosphorus to form phosphorus trichloride.

(a) Draw a diagram showing the arrangement of the valency electrons in one molecule of the covalent compound, phosphorus trichloride.

Use x to represent an electron from a phosphorus atom. Use o to represent an electron from a chlorine atom.

[2]

(b) Phosphorus trichloride reacts with water to form two acids.

(i) Balance the equation for this reaction.

PCl 3 + .......H2O → .......HCl + H3PO3[1]

(ii) Describe how you could show that phosphorus acid, H3PO3, is a weaker acid than hydrochloric acid.

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

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

.............................................................................................................................. [3]

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(iii) Two salts of phosphorus acid are its sodium salt, which is soluble in water, and its calcium salt which is insoluble in water. Suggest a method of preparation for each of these salts from aqueous phosphorus acid. Specify any other reagent needed and briefl y outline the method.

sodium salt ................................................................................................................

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

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

.............................................................................................................................. [2]

calcium salt ................................................................................................................

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

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

.............................................................................................................................. [2]

[Total: 10]

8 Hydrocarbons are compounds which contain only carbon and hydrogen.

(a) 20 cm3 of a gaseous hydrocarbon was burned in 120 cm3 of oxygen, which is in excess. After cooling, the volume of the gases remaining was 90 cm3. Aqueous sodium hydroxide was added to remove carbon dioxide, 30 cm3 of oxygen remained. All volumes were measured at r.t.p..

(i) Explain why it is essential to use excess oxygen.

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

.............................................................................................................................. [2]

(ii) Carbon dioxide is slightly soluble in water. Why does it dissolve readily in the alkali, sodium hydroxide?

.............................................................................................................................. [1]

(iii) Complete the following.

volume of gaseous hydrocarbon = ...............cm3

volume of oxygen used = .............cm3

volume of carbon dioxide formed = .............cm3 [2]

(iv) Use the above volume ratio to fi nd the mole ratio in the equation below and hence fi nd the formula of the hydrocarbon.

........CxHy(g) + ........O2(g) → ........CO2(g) + ........H2O(l)

hydrocarbon formula = ................................................ [2]

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(b) Alkanes are hydrocarbons and are generally unreactive. Their reactions include combustion, substitution and cracking.

(i) Chlorine reacts with butane in a substitution reaction.

CH3 — CH2 — CH2 — CH3 + Cl 2 → CH3 — CH2 — CH2 — CH2 — Cl + HCl

Give the structural formula of another possible product of this reaction.

[1]

(ii) What is the essential condition for this reaction?

.............................................................................................................................. [1]

(iii) Explain what is meant by cracking. Give an example of a cracking reaction and explain why the process is used.

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

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

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

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

.............................................................................................................................. [4]

[Total: 13]

13


33 Air containing an acidic impurity was neutralised by passing it through a column containing substance X.

acidic air neutralised air

substance X

What is substance X?

A calcium oxide

B sand

C sodium chloride

D concentrated sulfuric acid 34 The structure of a compound is shown.

C

H

C

O

O H

HH

H

CCH

Which functional groups are present in this compound?

alcohol alkene carboxylic acid

A � � �

B � � �

C � � �

D � � �

35 Which fraction from the fractional distillation of petroleum does not match its correct use?

fraction use

A fuel oil domestic heating

B kerosene jet fuel

C naphtha making roads

D refinery gas for heating and cooking

14

© UCLES 2012 0620/11/M/J/12

36 The diagram shows apparatus used to separate petroleum into four fractions.

petroleum

on rock wool

heat

thermometer

water

fraction

Which fraction contains the smallest hydrocarbon molecules?

fraction boiling point range / °C

A up to 70

B 70 to 120

C 120 to 170

D over 170

37 When a long chain hydrocarbon is cracked, the following products are produced.

1 C3H8

2 C2H4

3 C3H6

4 C2H6

Which products would decolourise bromine water?

A 1 and 4 B 2 and 3 C 2 only D 3 only

15

© UCLES 2012 0620/11/M/J/12

38 PVA is a polymer. The monomer has the structure shown.

C C

O H

H

H

H

To which homologous series does this compound belong?

alcohols alkenes

A � �

B � �

C � �

D � �

39 Which equation represents incomplete combustion of ethane?

A C2H6 + O2 → 2CO + 3H2

B C2H6 + 2O2 → 2CO2 + 3H2

C 2C2H6 + 5O2 → 4CO + 6H2O

D 2C2H6 + 7O2 → 4CO2 + 6H2O 40 Ethanol is an important chemical produced by the ……1…… of ……2…… .

Which words correctly complete gaps 1 and 2?

1 2

A combustion ethane

B combustion glucose

C fermentation ethane

D fermentation glucose

7


ForExaminer’s

Use

(e) (i) Complete the table below to show:

● the molecular formula for ethanoic acid ● the full structural formula for ethanol.

ethanoic acid ethanol

full structural formula C

H

H

C

O

O H

H

molecular formula C2H6O

[2]

(ii) Ethanol can be manufactured by the catalytic addition of steam to ethene. Complete the equation for this reaction.

............ + .......... → C2H5OH[1]

[Total: 14]

8

0620/21/M/J/12© UCLES 2012

ForExaminer’s

Use

4 Fractional distillation is used to separate petroleum into different fractions. Each fraction has a particular use.

(a) Match the fractions on the left with their uses on the right. The fi rst one has been done for you.

heating

fuel for ships

surfacing roads

waxes and polishes

making chemicals

gas oil

bitumen


refinery gases

naphtha

[4]

(b) Petroleum fractions contain hydrocarbons. What do you understand by the term hydrocarbon ?

..................................................................................................................................... [1]

(c) Methane, CH4, is a hydrocarbon.

(i) Draw the structure of methane, showing all atoms and bonds.

[1]

(ii) Complete the following equation for the burning of methane in excess oxygen.

CH4 + .....O2 → .......... + 2H2O[2]

9


ForExaminer’s

Use

(iii) Methane belongs to a homologous series called the alkanes. What do you understand by the term homologous series ?

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

.............................................................................................................................. [2]

(iv) Name the second member of the alkane homologous series.

.............................................................................................................................. [1]

[Total: 11]

10

0620/22/M/J/12© UCLES 2012

ForExaminer’s

Use

6 The diagram shows a fractionating column used to separate different hydrocarbon fractions in an oil refi nery.

petroleum

refinery gas

fractions

gasoline

A

kerosene

diesel oil

fuel oil

lubricating oil

bitumen

(a) On the diagram, draw an X to show the place in the column where the temperature is the highest. [1]

(b) State the name of the fraction labelled A.

..................................................................................................................................... [1]

(c) State a use for

the kerosene fraction, .......................................................................................................

the diesel oil fraction. .................................................................................................. [2]

11


ForExaminer’s

Use

(d) Complete the following sentences about fractional distillation using words from the list below.

boiling condenses cooled heated higher

lower melting mixture pressure vaporises

Petroleum is a ............................ of hydrocarbons. This mixture is ............................

and the hydrocarbons vaporise. The temperature in the fractionating column is

............................ at the top than at the bottom. As the vapours move up the column,

each hydrocarbon fraction ............................ when the temperature in the column falls

below the ............................ point of the hydrocarbon fraction. [5]

(e) The structures of four hydrocarbons, A, B, C and D, are shown below.

A

CH

H

H

C C

H

H

H

H

H

B

CH

H

H

C C

H

H

C

H

H

H

H

H

C D

C

H

H

C C

H

H

C

H

H

H

H

C

H

C C

H

H

H

H

H C

H

H

(i) Which two of these structures A, B, C or D have the same relative molecular mass?

.......................................................... and .......................................................... [1]

(ii) Which two of these structures A, B, C or D will decolourise aqueous bromine?

.......................................................... and .......................................................... [2]

[Total: 12]

5


ForExaminer’s

Use

(c) Vanadium(V) oxide is used to catalyse the exothermic reaction between sulfur dioxide and oxygen in the Contact Process.

2SO2 + O2 2SO3

The rate of this reaction can be increased either by using a catalyst or by increasing the temperature. Explain why a catalyst is used and not a higher temperature.

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

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

..................................................................................................................................... [2]

(d) The oxidation states of vanadium in its compounds are V(+5), V(+4), V(+3) and V(+2). The vanadium(III) ion can behave as a reductant or an oxidant.

(i) Indicate on the following equation which reactant is the oxidant.

2V3+ + Zn → 2V2+ + Zn2+

[1]

(ii) Which change in the following equation is oxidation? Explain your choice.

V3+ + Fe3+ → V4+ + Fe2+

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

.............................................................................................................................. [2]

[Total: 8]

5 Reactive metals tend to have unreactive compounds. The following is part of the reactivity series.

sodium most reactive calcium zinc copper silver least reactive

(a) Sodium hydroxide and sodium carbonate do not decompose when heated. The corresponding calcium compounds do decompose when heated. Complete the following equations.

calcium carbonate →....................................

....................................+

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

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

Ca(OH)2 → ................ + ................ [2]

6

0620/31/M/J/12© UCLES 2012

ForExaminer’s

Use

(b) All nitrates decompose when heated.

(i) The equation for the thermal decomposition of silver(I) nitrate is given below.

2AgNO3 → 2Ag + 2NO2 + O2

What are the products formed when copper(II) nitrate is heated?

.............................................................................................................................. [1]

(ii) Complete the equation for the action of heat on sodium nitrate.

..........NaNO3 → ........................ + ........................[2]

(c) Which of the metals in the list on page 5 have oxides which are not reduced by carbon?

..................................................................................................................................... [1]

(d) Choose from the list on page 5, metals whose ions would react with zinc.

..................................................................................................................................... [2]

[Total: 8]

6 Butane is an alkane. It has the following structural formula.

CH H

H

H

C

H

H

C

H

H

C

H

H

(a) The equation for the complete combustion of butane is given below. Insert the two missing volumes.

2C4H10(g) + 13O2(g) → 8CO2(g) + 10H2O(g)

.......... .......... 40 volume of gas / cm3

[2]

(b) Butane reacts with chlorine to form two isomers of chlorobutane.

(i) What type of reaction is this?

.............................................................................................................................. [1]

(ii) Explain the term isomer.

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

.............................................................................................................................. [2]

7


ForExaminer’s

Use

(iii) Draw the structural formulae of these two chlorobutanes.

[2]

(c) One of the chlorobutanes reacts with sodium hydroxide to form butan-1-ol. Butan-1-ol can be oxidised to a carboxylic acid.

(i) State a reagent, other than oxygen, which will oxidise butan-1-ol to a carboxylic acid.

.............................................................................................................................. [1]

(ii) Name the carboxylic acid formed.

.............................................................................................................................. [1]

(iii) Butan-1-ol reacts with ethanoic acid to form an ester. Name this ester and give its structural formula showing all the individual bonds.

name ................................................................................................................... [1]

structural formula

[2]

[Total: 12]

8

0620/31/M/J/12© UCLES 2012

ForExaminer’s

Use

7 Plastics are polymers. They are formed from their monomers by polymerisation.

(a) Two methods for the disposal of waste plastics are

● burning ● recycling.

Describe one advantage and one disadvantage of each method.

burning ..............................................................................................................................

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

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

recycling ...........................................................................................................................

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

..................................................................................................................................... [4]

(b) (i) There are two types of polymerisation reaction. Give their names and explain the differences between them.

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

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

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

.............................................................................................................................. [4]

(ii) Give the structural formula of a polymer which is formed from two different monomers.

[2]

[Total: 10]

8

0620/32/M/J/12© UCLES 2012

ForExaminer’s

Use

7 The alkenes are unsaturated hydrocarbons. They form a homologous series, the members of which have similar chemical properties:

● easily oxidised ● addition reactions ● polymerisation ● combustion.

(a) All the alkenes have the same empirical formula.

(i) State their empirical formula.

.............................................................................................................................. [1]

(ii) Why is the empirical formula the same for all alkenes?

.............................................................................................................................. [1]

(b) Alkenes can be oxidised to carboxylic acids by boiling with aqueous potassium manganate(VII).

(i) Pent-2-ene, CH3–CH2–CH=CH–CH3, oxidises to CH3–CH2–COOH and CH3COOH. Name these two acids.

CH3–CH2–COOH .......................................................................................................

CH3COOH ............................................................................................................ [2]

(ii) Most alkenes oxidise to two carboxylic acids. Deduce the formula of an alkene which forms only one carboxylic acid.

[1]

(c) Complete the following equations for the addition reactions of propene.

(i) CH3–CH=CH2 + Br2 → .................................... [1]

(ii) CH3–CH=CH2 + H2O → .................................... [1]

(d) Draw the structural formula of poly(propene)

[2]

9


ForExaminer’s

Use

(e) 0.01 moles of an alkene needed 2.4 g of oxygen for complete combustion. 2.2 g of carbon dioxide were formed. Determine the following mole ratio.

moles of alkene : moles of O2 : moles of CO2

From this ratio determine the formula of the alkene.

..................................................................................................................................... [3]

Write an equation for the complete combustion of this alkene.

..................................................................................................................................... [1]

[Total: 13]

8 Ethylamine, CH3–CH2–NH2, is a base which has similar properties to ammonia.

(a) In aqueous ethylamine, there is the following equilibrium.

CH3–CH2–NH2 + H2O CH3–CH2–NH3+ + OH–

Explain why water is behaving as an acid in this reaction.

..................................................................................................................................... [1]

(b) Given aqueous solutions of ethylamine and sodium hydroxide, describe how you could show that ethylamine is a weak base like ammonia and not a strong base like sodium hydroxide.

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

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

..................................................................................................................................... [3]

(c) Ethylamine, like ammonia, reacts with acids to form salts.

CH3–CH2–NH2 + HCl → CH3–CH2–NH3Cl

ethylammonium chloride

Suggest how you could displace ethylamine from the salt, ethylammonium chloride.

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

..................................................................................................................................... [2]

34 Two uses of oxygen are

1 burning acetylene in welding,

2 helping the breathing of hospital patients.

Which of these uses form carbon dioxide?

35 Lime is used to treat an industrial waste.

Which pH change occurs in the treatment?

untreated waste → treated waste

A acidic → neutral

B alkaline → acidic

C alkaline → neutral

D neutral → acidic

36 A compound Q has the structure shown.

What is the name of Q?

A heptane

B heptanoic acid

C heptanol

D heptene

H

H

H C

H

H

C

H

H

C

H

H

C

H

H

C

H

H

C

H

H

HC O

untreatedwaste

lime

treatedwaste

13

0620/1/O/N/02 [Turn over

A

B

C

D

use 1

�

�

✗

✗

use 2

�

✗

�

✗

37 A student sets up the apparatus shown to separate petroleum into its different liquid parts.

Why does this method of separation work?

The liquids in petroleum have different

A boiling points,

B densities,

C functional groups,

D melting points.

38 Which row in the table correctly shows properties of decane?

themometer

coldwater

heat

petroleumon rock wool

14

0620/1/O/N/02

A

B

C

D

burns

�

�

✗

✗

is unsaturated

�

✗

�

✗

39 The equation shows the cracking of a hydrocarbon.

Which compounds are unsaturated?

A X only B Y only C X and Z D Y and Z

40 A student states that

ethanol reacts with water to form beer and wine;

ethanol and water are used as solvents in industry.

Which of the underlined words are correct?

H

H HH

C C

H

HC

H

HC C C CC

H HH

H

H H H

H

H

H HH

= – – – –+

X Y Z

15

0620/1/O/N/02

A

B

C

D

reacts

�

�

✗

✗

solvents

�

✗

�

✗

0620/2 Nov02

8

4 Some organic compounds found in ripe fruits are shown below.

CH3CO

2H CH

3CH

2CH

2CO

2H

CH3CH

2OH CH

3CH

2CHO

(a) What do you understand by the term organic compound?

[1]

(b) Which two of the compounds belong to the same homologous series?

compound and compound [1]

(c) Which one of these compounds is an unsaturated hydrocarbon?

[1]

(d) Which one of these compounds is an alcohol?

[1]

(e) Which one of these compounds can be formed directly by cracking the paraffin fraction

from petroleum?

[1]

(f) Compound D burns readily.

(i) Burning is an exothermic reaction.

Explain the meaning of the term exothermic.

[1]

(ii) State the products formed when D burns in excess air.

[2]

A

B C

D E

For

Examiner’s

Use

C

C

H

H H

H

0620/2 Nov 2002 Turn over

9

(iii) Name the carbon compound formed when D undergoes incomplete

combustion.

[1]

(g) Write down the molecular formula of compound C.

[1]

(h) Calculate the relative molecular mass of compound C.

[1]

(i) Many fruits contain a variety of different coloured compounds.

What separation technique can you use to separate these different coloured

compounds?

[1]

For

Examiner’s

Use

8

0620/3/O/N/02

5 Alkenes are unsaturated hydrocarbons. They show structural isomerism. Alkenes take partin addition reactions and form polymers.

(a) Structural isomers have the same molecular formula but different structural formulae.Give an example of structural isomerism.

molecular formula .............................................................................................................

two structural formulae

[3]

(b) Ethene reacts with each of the following. Give the name and structural formula of eachproduct.

(i) steam

name of product ..........................................................

structure of product

[2]

(ii) hydrogen

name of product ...........................................................

structure of product

[2]

ForExaminer’s

Use

9

0620/3/O/N/02

(c) Alkenes polymerise by addition.

(i) Explain the term polymerise.

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

...............................................................................................................................[2]

(ii) What is the difference between addition polymerisation and condensationpolymerisation?

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

...............................................................................................................................[2]

(iii) Poly(dichloroethene) is used extensively to package food. Draw its structure. Thestructural formula of dichloroethene is drawn below.

[2]

(d) Steel may be coated with another metal, eg zinc or chromium, or with a polymer, egpoly(chloroethene), to prevent rusting.

(i) Suggest a property of poly(chloroethene) that makes it suitable for this purpose.

...............................................................................................................................[1]

(ii) Explain why the steel will rust when the protective coating of chromium or polymeris broken.

...............................................................................................................................[1]

(iii) When the protective layer of zinc is broken, the steel still does not rust.Suggest an explanation.

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

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

...............................................................................................................................[2]

C CCl

Cl

H

H

ForExaminer’s

Use

15

0620/01 O/N/03 [Turn over

34 Two processes are listed.

1 treating acidic soil with slaked lime

2 using limestone to extract iron

In which of these processes is carbon dioxide produced?

35 Organic compounds may have names ending in –ane, -ene, -ol or –oic acid.

How many of these endings indicate the compounds contain double bonds in their molecules?

A 1 B 2 C 3 D 4

36 Which compound is unsaturated and forms a neutral solution in water?

37 Which fraction produced by the distillation of petroleum is used as aircraft fuel?

A bitumen

B diesel

C paraffin

D petrol

CH2OH

CH

CH

CH2OH

CH2OH

CH2

CH2

CH2OH

CO2H

CH

CH

CO2H

CO2H

CH2

CH2

CO2H

A B C D

A

B

C

D

1 2

✓

✓

✗

✗

✓

✗

✓

✗

16

0620/01 O/N/03

38 The diagram shows the structures of two compounds.

The two compounds have similar chemical properties.

Why is this?

Their molecules have the same

A functional group.

B number of carbon atoms.

C number of oxygen atoms.

D relative molecular mass.

H C OC C

H H H

H H H

H H C C C

H H H

H O H

H

H

3


(b) State the name given to the method of separation shown in

(i) diagram A, .................................................................................................................

(ii) diagram B. .................................................................................................................[2]

(c) Method A can be modified to separate petroleum into useful fractions.The diagram below shows the different fractions obtained from a fractionating column.

(i) Which of these fractions has the lowest boiling point?

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

(ii) State one use for each of the following fractions.

paraffin ......................................................................................................................

bitumen .....................................................................................................................[3]

(d) Petroleum is a mixture of organic compounds. Which one of the following best describes the compounds found in petroleum?Put a ring around the correct answer.

acids alcohols carbohydrates hydrocarbons[1]

fractions

fuel gas

petrol

paraffin

light gas oil

diesel


bitumen

crude oil

ForExaminer’s

Use

4

0620/2/O/N/03

(e) Before petroleum is fractionated, it is often heated to remove dissolved natural gas. Most of this natural gas is methane, CH4.Draw a diagram to show how the electrons are arranged in methane.

show hydrogen electrons as •show carbon electrons as �

[2]

(f) Methane, ethane and propane belong to a particular homologous series of compounds.State the name of the homologous series to which these three compounds belong.

..........................................................................................................................................[1]

ForExaminer’s

Use

5


(ii) How could you show that this reaction is photochemical?

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

...............................................................................................................................[1]

(c) Photosynthesis is another example of a photochemical reaction. Glucose and morecomplex carbohydrates are made from carbon dioxide and water.

(i) Complete the equation.

6CO2 + 6H2O → C6H12O6 + ……….. [2]

(ii) Glucose can be represented as

Draw the structure of a more complex carbohydrate that can be formed fromglucose by condensation polymerisation.

[2]

3 Zinc blende is the common ore of zinc. It is usually found mixed with an ore of lead andtraces of silver.

(a) (i) Describe how zinc blende is changed into zinc oxide.

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

...............................................................................................................................[2]

(ii) Write an equation for the reduction of zinc oxide by carbon.

...............................................................................................................................[2]

(iii) The boiling point of lead is 1740 °C and that of zinc is 907 °C. Explain why, whenboth oxides are reduced by heating with carbon at 1400 °C, only lead remains inthe furnace.

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

...............................................................................................................................[2]

HO OH

ForExaminer’s

Use

7


4 Esters occur naturally in plants and animals. They are manufactured from petroleum. Ethylethanoate and butyl ethanoate are industrially important as solvents.

(a) (i) Explain the term solvent.

...............................................................................................................................[1]

(ii) Give the formula of ethyl ethanoate.

[1]

(iii) Ethyl ethanoate can be made from ethanol and ethanoic acid. Describe how thesechemicals can be made.

ethanol from ethene

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

...............................................................................................................................[2]

ethanoic acid from ethanol

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

...............................................................................................................................[2]

(iv) Name two chemicals from which butyl ethanoate can be made.

...............................................................................................................................[1]

(b) The following equation represents the alkaline hydrolysis of a naturally occurring ester.

(i) Which substance in the equation is an alcohol? Underline the substance in theequation above.

[1]

(ii) What is the major use for compounds of the type C17H35COONa ?

...............................................................................................................................[1]

C17H35 CH2CO2

C17H35 CHCO2

C17H35

+ 3NaOH 3C17H35COONa

CH2

CH2OH

CHOH

CH2OHCO2

+

ForExaminer’s

Use

8

0620/03/O/N/03

(c) A polymer has the structure shown below.

(i) What type of polymer is this?

...............................................................................................................................[1]

(ii) Complete the following to give the structures of the two monomers from which theabove polymer could be made.

[2]

(d) Esters are frequently used as solvents in chromatography. A natural macromoleculewas hydrolysed to give a mixture of amino acids. These could be identified bychromatography.

(i) What type of macromolecule was hydrolysed?

..................................................................................................................................[1]

(ii) What type of linkage was broken by hydrolysis?

..................................................................................................................................[1]

(iii) Explain why the chromatogram must be sprayed with a locating agent before theamino acids can be identified.

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

...............................................................................................................................[1]

(iv) Explain how it is possible to identify the amino acids from the chromatogram.

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

...............................................................................................................................[2]

C

O O

C O O

ForExaminer’s

Use

14

� UCLES 2004 0620/1/O/N/04

33 Which statement explains why iron is used as the catalyst in the manufacture of ammonia?

A More ammonia is produced in a given time.

B The catalyst is unchanged at the end of the reaction.

C The catalyst neutralises the ammonia.

D The purity of the ammonia is improved.

34 A sample of acid rainwater (pH = 4) is passed down a glass column packed with marble chippings(calcium carbonate). The water coming from the bottom of the column is collected in a beaker.The pH is now 6.

rainwater

marblechippings

water

What causes the change in pH?

A The acid has been filtered.

B The acid has been neutralised.

C The acid is made more concentrated.

D The acid is precipitated.

35 What are the products when limestone (calcium carbonate) is strongly heated?

A calcium hydroxide and carbon dioxide

B calcium hydroxide and carbon monoxide

C calcium oxide and carbon dioxide

D calcium oxide and carbon monoxide

36 Which compound is ethanol?

C

H

H

OH H

A

C

H

H

CH

H

H

O H

B

H C

O

O

H

C

C

H

H

CH

O

O

H

D

15

� UCLES 2004 0620/1/O/N/04

37 What is petroleum?

A an aircraft fuel

B a central heating fuel

C a mixture of carbohydrates

D a mixture of hydrocarbons

38 Methanol and ethanol belong to the same homologous series.

What does this mean?

A Their molecules contain atoms only of carbon and hydrogen.

B Their molecules have the same number of carbon atoms.

C They have the same functional group.

D They have the same relative molecular mass.

39 Which substances can be obtained by cracking hydrocarbons?

A ethanol and ethene

B ethanol and hydrogen

C ethene and hydrogen

D ethene and poly(ethene)

40 The apparatus shown may be used to study the products of fermentation.

fermentingsolution

aqueouscalciumhydroxide

What is the purpose of the aqueous calcium hydroxide?

A to absorb any excess of yeast

B to condense the ethanol produced

C to prevent air entering the system

D to show that carbon dioxide is produced

4

� UCLES 2004 0620/02/O/N/04

For

Examiner’s

Use

2 The structures of some compounds found in plants are shown below.

H

N

H

H

C

O

O

H

H

C

H

H

H

H

C

O

O

CH

H

H

C

H

H

C HO

H

C

CC

C

C

H

H

H

H

HH

H

H H

C C

H

H

H

H

B C

D E

A

(a) Which two of these compounds are unsaturated hydrocarbons?

[1]

(b) Which two of these compounds contain a carboxylic acid functional group?

[1]

(c) Write the molecular formula for compound D.

[1]

(d) Draw the structure of the product formed when compound A reacts with bromine.

Show all atoms and all bonds.

[1]

5

� UCLES 2004 0620/02/O/N/04 [Turn over

For

Examiner’s

Use

(e) Strawberry fruits produce compound A (ethene) naturally.

A scientist left some green strawberry fruits to ripen.

The scientist measured the concentration of ethene and carbon dioxide produced bythe strawberry fruits over a ten day period.

The graph below shows the results.

00 2 4 6 8 10

100

200

300

400

days

concentration

of gas/parts

per million

(ppm)

carbon dioxide

ethene

(i) Between which two days does the rate of ethene production increase most rapidly?

[1]

(ii) What is the name given to the process in which carbon dioxide is produced byliving organisms?

Put a ring around the correct answer.

acidification combustion neutralization respiration[1]

(iii) Carbon dioxide concentration over 350 ppm has an effect on ethene production bythe fruits.

What effect is this?

[1]

(iv) Ethene gas spreads throughout the fruit by a random movement of molecules.

What is the name given to the random movement of molecules?

Put a ring around the correct answer.

aeration diffusion evaporation ionisation[1]

6

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(v) Ethene gas promotes the ripening of strawberry fruits.

Ripening of strawberries is slowed down by passing a stream of nitrogen over thefruit.

Suggest why this slows down the ripening process.

[1]

(vi) Enzymes are involved in the ripening process.

What is an enzyme?

[2]

(f) Plants make a variety of coloured pigments.A student extracted red colouring from four different plants, R, S, T and U.The student put a spot of each colouring on a piece of filter paper.The filter paper was dipped into a solvent and left for 30 minutes.The results are shown below.

R S T U R S T U

start of experiment result after 30 minutes

filter paper

solvent

(i) What is name given to the process shown in the diagram?

[1]

(ii) Which plant contained the greatest number of different pigments?

[1]

(iii) Which two plants contained the same pigments?

[1]

14

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(f) The hydrogen obtained by electrolysis can be used in the manufacture of margarine.

C

H

H

C

H

H

C C

H H

CO2HH

n

C

H

H

C

H

H H H

C C

H H

CO2HH+ H2

n

Ni

(i) Complete the following sentences about this reaction using words from the list.

catalystinhibitormonomericsaturatedunsaturated

Hydrogen gas is bubbled through carbon compounds

using a nickel which speeds up the reaction.

The margarines produced are compounds. [3]

(ii) State one other use of hydrogen.

[1]

5

© UCLES 2004 0620/03/O/N/04 [Turn over

For

Examiner’s

Use

3 The simplest alcohol is methanol. (a) It is manufactured by the following reversible reaction.

CO (g) + 2H2 (g) CH3OH (g) 300

oC 30atm (i) Reversible reactions can come to equilibrium. Explain the term equilibrium.

[1]

(ii) At 400

oC, the percentage of methanol in the equilibrium mixture is lower than at 300

oC. Suggest an explanation.

[2]

(iii) Suggest two advantages of using high pressure for this reaction. Give a reason for each advantage.

advantage

reason

advantage

reason

[5]

6

.

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(b) (i) Complete the equation for the combustion of methanol in an excess of oxygen.

CH3OH + O2 + [2]

(ii) Complete the word equation.

methanol + ethanoic acid +

[2]

(iii) Methanol can be oxidised to an acid. Name this acid.

[1]

10

.

© UCLES 2004 0620/03/O/N/04

For

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Use

6 Polymers are extensively used in food packaging. Poly(dichloroethene) is used because gases can only diffuse through it very slowly. Polyesters have a high thermal stability and food can be cooked in a polyester bag.

(a) (i) The structure of poly(dichloroethene) is given below.

H Cl

C C

H Cl

n Draw the structural formula of the monomer.

(ii) Explain why oxygen can diffuse faster through the polymer bag than carbon dioxide can.

[2]

(b) (i) A polyester can be formed from the monomers HO-CH2CH2-OH and HOOC-C6H4-COOH. Draw the structure of this polyester.

[2]

[1]

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For

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(Ii) Name a naturally occurring class of compounds that contains the ester linkage.

[1]

(iii) Suggest what is meant by the term thermal stability.

[1]

(c) (i) Describe two environmental problems caused by the disposal of plastic (polymer)

waste.

[2]

(ii) The best way of disposing of plastic waste is recycling to form new plastics. What

is another advantage of recycling plastics made from petroleum?

[1]

13


For

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Use

8 The alkenes are a homologous series of unsaturated hydrocarbons. (a) The table below gives the names, formulae and boiling points of the first members of

the series.

name formula boiling point / oC

ethene C2H4 -102

propene C3H6 -48

butene C4H8 -7

pentene C5H10 30

hexene

(i) Complete the table by giving the formula of hexene and by predicting its boiling point. [2]

(ii) Deduce the formula of the alkene which has a relative molecular mass of 168.

Show your working.

[2]

(b) Describe a test that will distinguish between the two isomers, but-2-ene and cyclobutane.

test

result with but-2-ene

result with cyclobutane [3]

14

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(c) Alkenes undergo addition reactions. (i) What class of organic compound is formed when an alkene reacts with water?

[1]

(ii) Predict the structural formula of the compound formed when hydrogen chloride

reacts with but-2-ene.

[1]

(iii) Draw the structure of the polymer formed from but-2-ene.

[2]

14

© UCLES 2005 0620/01/O/N/05

34 Some students are asked to draw the structure of propanol.

Which diagram should the students draw?

C

H

H

C

H

H

O HCH

H

H

C

H

H

C

H

H

C

H

H

HH

C

H

H

CO

O

H

CH

H

H

C

H

H

CH

HC

H

HA

B

C

D

35 Acetylene is an unsaturated hydrocarbon used with oxygen in a welding torch.

Which diagram shows a molecule of acetylene?

key

= C

= H

= O

A B C D

15


36 The table shows the composition of natural gas.

gas % of natural gas

X 93.1

ethane 3.4

nitrogen 2.3

What is X?

A ethanol

B ethene

C methane

D propane 37 Which pair of compounds belong to the same homologous series?

A CH3CH3 and CH3CH2CH3

B CH3CH2OH and CH3OCH2CH3

C CH2CHCH2CH3 and CH3CH2CH2CH3

D CH3CH2OH and CH2CHCH2OH 38 The diagram shows the structure of an important product.

C

H

H

C

H

H

C

H

H

C

H

H

C

H

H

C

H

H

This product is formed by …..1….. of an …..2…..

Which words correctly complete gaps 1 and 2?

1 2

A addition polymerisation alkane

B addition polymerisation alkene

C cracking alkane

D cracking alkene

16

© UCLES 2005 0620/01/O/N/05

39 An organic compound has the structure shown.

C

C

C

C

C

CH

H

H

H

H

H

H H

H H

H

H

From knowledge of the properties of alkanes and alkenes, which reactions would be predicted for this compound?

burn decolourise aqueous bromine

A � �

B � �

C � �

D � �

40 Ethanol can be formed by

1 fermentation,

2 reaction between steam and ethene.

Which of these processes uses a catalyst?

1 2

A � �

B � �

C � �

D � �

11


For

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Use

5 The structures of some organic compounds are shown below.

CH

H

C

H

HH

C

H

H

C

H

H

H CH

H

C

H

HH

C

H

H

C

H

H

O HCH

H

H

H

A B

CH

H

C

H

H

C

H

C

H

H

H

D

CH

H

C

O

OH

H

E

C

(a) Name compound A.

[1]

(b) Which two of the compounds A to E belong to the same homologous series?

[1]

(c) (i) Which one of the compounds A to E has the same functional group as ethanol?

[1]

(ii) Draw the structure of ethanol, showing all atoms and bonds. [2] (iii) Describe how ethanol is made in industry from ethene.

[2]

12

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(d) (i) Which one of the compounds A to E is an unsaturated hydrocarbon?

[1]

(ii) Describe a chemical test for an unsaturated hydrocarbon.

test

result [2]

(e) Compound E is acidic. (i) State the name of compound E.

[1]

(ii) Describe a test to show that compound E is acidic.

test

result [2]

13

UCLES 2006 0620/01/O/N/06 [Turn over

34 The diagram shows a kiln used to heat limestone.

gas burners

product

air

waste gases

limestone

What is the product and what waste gas is formed?

product waste gas

A lime carbon monoxide

B lime carbon dioxide

C slaked lime carbon monoxide

D slaked lime carbon dioxide


CH3 CH3CH2

CH3

CH CH3 CH2CH2 CH CH3 CCH2

O H

O

X Y Z

What are X, Y and Z?

X Y Z

A alkane alkene alcohol

B alkane alkene carboxylic acid

C alkene alkane alcohol

D alkene alkane carboxylic acid

14

UCLES 2006 0620/01/O/N/06

36 How many oxygen atoms and double bonds are there in one molecule of ethanoic acid?

number of oxygen atoms number of double bonds

A 1 0

B 1 1

C 2 0

D 2 1

37 Compounds R and S occur naturally.

R is C6H14 and S is C6H12O6.

Which of the terms hydrocarbon and occurs in crude oil describe R and S?

hydrocarbon occurs in crude oil

A R only R only

B R only S only

C S only R only

D S only S only

38 The diagram shows an ethane molecule.

H H

H H

H H

C C

Which compound has chemical properties similar to those of ethane?

H

H H

H H

C C

H

H

HCH

H H

H H

C C O HH

H

H

C C

O

O

H

A B C D

C C

H

H

H

H

15

UCLES 2006 0620/01/O/N/06 [Turn over

39 The diagram shows the first four members of a homologous series.

H C H

H

H

H C C

H

H

H

H

H

H C C

H

H

C

H

H

H

H

H

H C C

H

H

C

H

H

C

H

H

H

H

H

What is the difference in molecular formula between one member and the next in the series?

A CH B CH2 C CH3 D CH4 40 The diagram shows part of a polymer.

C C

H

H

C

H

H

C

H

H

H

H

C C

H

H

H

H

Which compound is used as the monomer?

A C2H4

B C2H6

C C6H12

D C6H14

12

© UCLES 2006 0620/03/O/N/06

For

Examiner's

Use

8 The three types of food are carbohydrates, proteins and fats. (a) Aqueous starch is hydrolysed to maltose by the enzyme amylase. The formula of maltose is:

HO OHO

Starch is hydrolysed by dilute sulphuric acid to glucose.

HO OH

(i) What is an enzyme?

[1]

(ii) Draw the structure of starch. [1] (iii) Name the technique that would show that the products of these two hydrolyses are

different.

[1]

(b) Proteins have the same linkage as nylon but there is more than one monomer in the

macromolecule. (i) Draw the structure of a protein. [2] (ii) What class of compound is formed by the hydrolysis of proteins?

[1]

13

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(c) Fats are esters. Some fats are saturated, others are unsaturated. (i) Write the word equation for the preparation of the ester, propyl ethanoate.

[2]

(ii) Deduce the structural formula of this ester showing each individual bond. [2] (iii) How could you distinguish between these two fats? Fat 1 has the formula

CH2 – CO2 – C17H33

CH – CO2 – C17H33

CH2 – CO2 – C17H33 Fat 2 has the formula

CH2 – CO2 – C17H35

CH – CO2 – C17H35

CH2 – CO2 – C17H35

test

result with fat 1

result with fat 2 [3]

(iv) Both of these fats are hydrolysed by boiling with aqueous sodium hydroxide. What

type of compounds are formed?

and [2]

16

© UCLES 2007 0620/01/O/N/07

37 Which statements about all polymers are correct?

1 They are compounds containing only carbon and hydrogen.

2 They are large molecules made from many smaller molecules.

3 They occur in nature.

1 2 3

A � � �

B � � �

C � � �

D � � �

38 Properties of some organic compounds include:

1 they burn;

2 they dissolve in water;

3 they polymerise.

Which of these properties does ethanol have?

1 2 3

A � � �

B � � �

C � � �

D � � �

39 Which two molecules contain the same number of hydrogen atoms?

A ethane and ethanoic acid

B ethane and ethene

C ethanoic acid and ethanol

D ethanoic acid and ethene

17

© UCLES 2007 0620/01/O/N/07

40 The structures of two compounds are shown.

CH3 CH2

CH3

CH CH3 CH3 CHCH2 CH2

P Q

Which line in the table is correct?

polymerises reacts readily with bromine

A P P

B P Q

C Q P

D Q Q

8

© UCLES 2007 0620/03/O/N/07

For

Examiner's

Use

6 The alcohols form a homologous series. The first four members are methanol, ethanol, propan-1-ol and butan-1-ol.

(a) One characteristic of a homologous series is that the physical properties vary in a

predictable way. The table below gives the heats of combustion of the first three alcohols.

alcohol formula heat of combustion in kJ / mol

methanol CH3OH -730

ethanol CH3-CH2-OH -1370

propan-1-ol CH3-CH2-CH2-OH -2020

butan-1-ol CH3-CH2-CH2-CH2-OH

(i) The minus sign indicates that there is less chemical energy in the products than in

the reactants. What form of energy is given out by the reaction?

[1]

(ii) Is the reaction exothermic or endothermic?

[1]

(iii) Complete the equation for the complete combustion of ethanol.

C2H5OH + O2 → + [2]

9


For

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(iv) Determine the heat of combustion of butan-1-ol by plotting the heats of combustion of the first three alcohols against the number of carbon atoms per molecule.

–700

–800

–900

–1000

–1100

–1200

–1300

–1400

–1500

–1600

–1700

–1800

–1900

–2000

–2100

–2200

–2300

–2400

–2500

–2600

–2700

–2800

1 2 3 4

number of carbon atoms per molecule

heat of

combustion /

kJ / mol

The heat of combustion of butan-1-ol = kJ / mol [3]

10

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(v) Describe two other characteristics of homologous series.

[2]

(b) Give the name and structural formula of an isomer of propan-1-ol. structural formula

name [2]

(c) Methanol is made from carbon monoxide.

CO(g) + 2H2(g) CH3OH(g) the forward reaction is exothermic (i) Describe how hydrogen is obtained from alkanes.

[2]

(ii) Suggest a method of making carbon monoxide from methane.

[2]

(iii) Which condition, high or low pressure, would give the maximum yield of methanol?

Give a reason for your choice.

pressure

reason [2]

(d) For each of the following predict the name of the organic product. (i) reaction between methanol and ethanoic acid

[1]

(ii) oxidation of propan-1-ol by potassium dichromate(VI)

[1]

(iii) removal of H2O from ethanol (dehydration)

[1]

[Total: 20]

14

© UCLES 2008 0620/01/O/N/08

37 When added in turn to four solutions, aqueous sodium carbonate gives the following results.

Which solution is acidic?

solution result

A a blue precipitate forms

B a white precipitate forms

C bubbles of gas form

D no visible reaction occurs

38 Which products are obtained by the cracking of an alkane?

alkene hydrogen water

A � � �

B � � �

C � � �

D � � �

39 A compound takes part in an addition reaction.

How does its name end?

A …..ane

B …..ene

C …..ol

D …..oic acid 40 When glucose is fermented, ethanol is formed together with

A carbon dioxide.

B ethene.

C methane.

D oxygen.

5


For

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4 Across the world, food safety agencies are investigating the presence of minute traces of the toxic hydrocarbon, benzene, in soft drinks. It is formed by the reduction of sodium benzoate by vitamin C.

INGREDIENTS

Orange juice,

sodium benzoate,

vitamin C

(a) Sodium benzoate is a salt, it has the formula C6H5COONa. It can be made by the neutralisation of benzoic acid by sodium hydroxide.

(i) Deduce the formula of benzoic acid.

[1]

(ii) Write a word equation for the reaction between benzoic acid and sodium hydroxide.

[1]

(iii) Name two other compounds that would react with benzoic acid to form sodium benzoate.

[2]

(b) Benzene contains 92.3% of carbon and its relative molecular mass is 78. (i) What is the percentage of hydrogen in benzene?

[1]

(ii) Calculate the ratio of moles of C atoms: moles of H atoms in benzene.

[2]

(iii) Calculate its empirical formula and then its molecular formula.

The empirical formula of benzene is

The molecular formula of benzene is [2]

6

© UCLES 2008 0620/31/O/N/08

For

Examiner's

Use

(c) The structural formula of Vitamin C is drawn below.

CC

CO C C C

OH H

HH H

OH

O

HO OH (i) What is its molecular formula?

[1]

(ii) Name the two functional groups which are circled.

[2]

[Total: 12]

10

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Use

7 The alkanes are generally unreactive. Their reactions include combustion, substitution and cracking.

(a) The complete combustion of an alkane gives carbon dioxide and water. (i) 10 cm3 of butane is mixed with 100 cm3 of oxygen, which is an excess. The mixture

is ignited. What is the volume of unreacted oxygen left and what is the volume of carbon dioxide formed?

C4H10(g) + (g)O622

1 4CO2(g) + 5H2O(l)

Volume of oxygen left = cm3

Volume of carbon dioxide formed = cm3 [2]

(ii) Why is the incomplete combustion of any alkane dangerous, particularly in an

enclosed space?

[2]

(b) The equation for a substitution reaction of butane is given below.

CH3−CH2−CH2−CH3 + Cl2 CH3−CH2−CH2−CH2 −Cl + HCl (i) Name the organic product.

[1]

(ii) This reaction does not need increased temperature or pressure. What is the essential reaction condition?

[1]

(iii) Write a different equation for a substitution reaction between butane and chlorine.

[1]

11

© UCLES 2008 0620/31/O/N/08

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Use

(c) Alkenes are more reactive and industrially more useful than alkanes. They are made by cracking alkanes.

C7H16 CH3−CH=CH2 + CH3−CH2−CH=CH2 + H2 heptane propene but−1−ene (i) Draw the structural formula of the polymer poly(propene). [2] (ii) Give the structural formula and name of the alcohol formed when but-1-ene reacts

with steam.

name [1]

structural formula [1] (iii) Deduce the structural formula of the product formed when propene reacts with

hydrogen chloride. [1] [Total: 12]

14

© UCLES 2009 0620/01/O/N/09

37 The apparatus shows an experiment used to test gas X.

gas X

orange bromine

solution

The bromine solution quickly becomes colourless.

What is the structure of gas X?

C C

H

H

H

H

B

H C

A

H

H

H H C

C

H

H

C

H

H

H H C

D

H

H

C

H

H

O H

38 Which statement about petroleum is not correct?

A It can be separated into useful substances by fractional distillation.

B It consists mainly of hydrocarbons.

C It is found underground in many parts of the world.

D Its main use is for making lubricants and polishes. 39 Butene and hexene belong to the same homologous series.

What is the same for butene and hexene?

A boiling point

B functional group

C number of hydrogen atoms per molecule

D relative molecular mass

15

© UCLES 2009 0620/01/O/N/09

40 The table shows the formulae of members of the alkane series.

name of compound formula

methane CH4

ethane C2H6

propane ?

butane C4H10

pentane C5H12

What is the formula of propane?

A C2H8 B C3H7 C C3H8 D C3H9

8

© UCLES 2009 0620/31/O/N/09

For

Examiner's

Use

5 The first three elements in Group IV are carbon, silicon and germanium. The elements and their compounds have similar properties. (a) The compound, silicon carbide, has a macromolecular structure similar to that of

diamond. (i) A major use of silicon carbide is to reinforce aluminium alloys which are used in

the construction of spacecraft. Suggest three of its physical properties.

[3]

(ii) Complete the following description of the structure of silicon carbide.

Each carbon atom is bonded to four atoms.

Each silicon atom is bonded to carbon atoms. [2]

(b) Germanium(IV) oxide, GeO2, has the same macromolecular structure as silicon(IV)

oxide. Draw the structural formula of germanium(IV) oxide. [3]

9


For

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(c) Germanium forms a series of hydrides comparable to the alkanes. (i) Draw the structural formula of the hydride which contains four germanium atoms

per molecule. [1] (ii) Predict the products of the complete combustion of this hydride.

[2]

[Total: 11]

11


For

Examiner's

Use

(b) Sulfuric acid was first made in the Middle East by heating the mineral, green vitriol, FeSO4.7H2O. The gases formed were cooled.

FeSO4.7H2O(s) → FeSO4(s) + 7H2O(g) green crystals yellow powder

2FeSO4(s) → Fe2O3(s) + SO2(g) + SO3(g)

On cooling

SO3 + H2O → H2SO4 sulfuric acid

SO2 + H2O → H2SO3 sulfurous acid (i) How could you show that the first reaction is reversible?

[2]

(ii) Sulfurous acid is a reductant. What would you see when acidified potassium

manganate(VII) is added to a solution containing this acid?

[2]

(iii) Suggest an explanation why sulfurous acid in contact with air changes into sulfuric

acid.

[1]

(c) 9.12 g of anhydrous iron(II) sulfate was heated. Calculate the mass of iron(III) oxide formed and the volume of sulfur trioxide, at r.t.p., formed.

2FeSO4(s) → Fe2O3(s) + SO2(g) + SO3(g)

mass of one mole of FeSO4 = 152 g

number of moles of FeSO4 used =

number of moles of Fe2O3 formed =

mass of one mole of Fe2O3 = g

mass of iron(III) oxide formed = g

number of moles of SO3 formed =

volume of sulfur trioxide formed = dm3

[6] [Total: 16]

12

© UCLES 2009 0620/31/O/N/09

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Examiner's

Use

7 Butan-1-ol is used as a solvent for paints and varnishes, to make esters and as a fuel. Butan-1-ol can be manufactured from but-1-ene, which is made from petroleum.

Biobutanol is a fuel of the future. It can be made by the fermentation of almost any form of biomass - grain, straw, leaves etc.

(a) But-1-ene can be obtained from alkanes such as decane, C10H22, by cracking. (i) Give the reaction conditions.

[2]

(ii) Complete an equation for the cracking of decane, C10H22, to give but-1-ene.

C10H22 → [2]

(iii) Name the reagent that reacts with but-1-ene to form butan-1-ol.

[1]

(b) (i) Balance the equation for the complete combustion of butan-1-ol.

C4H9OH + O2 → CO2 + H2O [2]

(ii) Write a word equation for the preparation of the ester butyl methanoate.

[2]

15


37 The diagram shows the structure of a compound.

H

C

H

C

H

H

C

H

O H

H

C

H

To which classes of compound does this molecule belong?

alkane alkene alcohol

A no no no

B no yes yes

C yes no yes

D yes yes yes

38 Which structures show compounds that are members of the same homologous series?

O C

H

H

C

H

H

C

H

H

H H

1

H C

H

H

C

H

H

C

O

O H

2

H C

H

H

C

H

H

C

H

H

H

C

3

H C

H

H

C

H

H

C

H

H

C

H

H

O H

4

A 1 and 2 B 1 and 4 C 2 and 3 D 3 and 4 39 Ethene reacts with Y to produce ethanol.

ethene + Y → ethanol

What is Y?

A hydrogen

B oxygen

C steam

D yeast

16

© UCLES 2010 0620/11/O/N/10

40 In an oil refinery, crude oil is separated into useful fractions.

The diagram shows some of these fractions.

pre-heat

400 °C

refinery gases

gasolene

X

diesel

Y

Z

What are fractions X, Y and Z?

X Y Z

A fuel oil bitumen paraffin (kerosene)

B fuel oil paraffin (kerosene) bitumen

C paraffin (kerosene) bitumen fuel oil

D paraffin (kerosene) fuel oil bitumen

8

0620/31/O/N/10© UCLES 2010

ForExaminer’s

Use

5 Monomers polymerise to form polymers or macromolecules.

(a) (i) Explain the term polymerise.

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

.............................................................................................................................. [1]

(ii) There are two types of polymerisation - addition and condensation. What is the difference between them?

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

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

.............................................................................................................................. [2]

(b) An important monomer is chloroethene which has the structural formula shown below.

C C

H

Cl

H

H

It is made by the following method.

C2H4 + Cl 2 → C2H4 Cl 2 dichloroethane

This is heated to make chloroethene.

C2H4Cl 2 → C2H3Cl + HCl

(i) Ethene is made by cracking alkanes. Complete the equation for cracking dodecane.

C12H26 → .................... + 2C2H4[1]

Another method of making dichloroethane is from ethane.

C2H6 + 2Cl 2 → C2H4Cl 2 + 2HCl

(ii) Suggest a reason why the method using ethene is preferred.

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

.............................................................................................................................. [1]

(iii) Describe an industrial method of making chlorine.

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

.............................................................................................................................. [2]

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(iv) Draw the structural formula of poly(chloroethene).

Include three monomer units.

[2]

[Total: 9]

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6 The alcohols form an homologous series.

(a) Give three characteristics of an homologous series.

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

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

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

..................................................................................................................................... [3]

(b) The following two alcohols are members of the series and they are isomers.

CH3 — CH2 — CH2 — CH2 — OH and (CH3)2CH — CH2OH

(i) Explain why they are isomers.

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

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

.............................................................................................................................. [2]

(ii) Give the structural formula of another alcohol which is also an isomer of these alcohols.

[1]

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(c) Copper(II) oxide can oxidise butan-1-ol to liquid X whose pH is 4.

liquid Xformed by

oxidation of

butan-1-ol.

heat

mineral wool

soaked in butan-1-ol copper(II) oxide

(i) Name another reagent which can oxidise butan-1-ol.

.............................................................................................................................. [1]

(ii) What type of compound is liquid X and what is its formula?

type of compound ............................................................................................... [1]

formula of liquid X

[1]

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34 Which combination of chemical compounds could be used to produce the fertiliser shown?

SUPERGROW

N P K

21 16 8: :

A NH4NO3, Ca3(PO4)2

B NH4NO3, CO(NH2)2

C NH4NO3, K2SO4, (NH4)2SO4

D (NH4)3PO4, KCl 35 Which pollutant gas is produced by the decomposition of vegetation?

A carbon monoxide

B methane

C nitrogen oxide

D sulfur dioxide 36 The diagram represents the molecule of an organic compound.

key

= carbon

= oxygen

= hydrogen

What is the name of the compound?

A ethane

B ethanoic acid

C ethanol

D ethene

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37 Petroleum is a very important raw material that is separated into more useful products.

Which terms describe petroleum and the method used to separate it?

petroleum is a method used to

separate petroleum

A compound cracking

B compound fractional distillation

C mixture cracking

D mixture fractional distillation

38 Which pair of compounds are members of the same homologous series?

A

C C

H

H

H

H

H C

H

H

C

H

H

H

B

H C

H

H

C

H

H

H

H C

H

H

C

H

C

H

H

H

H

D

H C

H

H

C

H

OH

H O

OH

H C

H

H

C

C

C C

H

H

H

H

C

H

H

C

Hn

H

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39 The table shows the composition of four different types of petroleum (crude oil).

fraction Arabian Heavy

/ % Arabian Light

/ % Iranian Heavy

/ % North Sea

/ %

gasoline 18 21 21 23

kerosene 11.5 13 13 15

diesel 18 20 20 24

fuel oil 52.5 46 46 38

Which type of petroleum is best for the motor vehicle industry?

A Arabian Heavy

B Arabian Light

C Iranian Heavy

D North Sea 40 When glucose is fermented, ethanol is formed together with

A carbon dioxide.

B ethene.

C methane.

D oxygen.

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6 Structural formulae are an essential part of Organic Chemistry.

(a) Draw the structural formula of each of the following. Show all the bonds in the structure.

(i) ethanoic acid

[1]

(ii) ethanol

[1]

(b) (i) Ethanoic acid and ethanol react to form an ester. What is the name of this ester?

.............................................................................................................................. [1]

(ii) The same linkage is found in polyesters. Draw the structure of the polyester which can be formed from the monomers shown below.

HOOC — C6H4 — COOH and HO — CH2 — CH2 — OH

[3]

(iii) Describe the pollution problems caused by non-biodegradable polymers.

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

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

.............................................................................................................................. [2]

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(c) Two macromolecules have the same amide linkage. Nylon, a synthetic polymer, has the following structure.

C

O

H

N

H

N

H

NC

O

C

O

H

NC

O

C

O

Protein, a natural macromolecule, has the following structure.

N C

OH H

N C

O H

N C

O OH

N C

How are they different?

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

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

..................................................................................................................................... [2]

[Total: 10]

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5 The alcohols form a homologous series. Two characteristics of a homologous series are that the physical properties of the members vary in a predictable way and they have similar chemical properties.

(a) Complete the table.

name formula mass of onemole / g

boiling point/ °C

methanol CH3 – OH 32 64

ethanol CH3 – CH2 – OH 46 78

propan-1-ol CH3 – CH2 – CH2 – OH 60 98

butan-1-ol CH3 – CH2 – CH2 – CH2 – OH 74 118

pentan-1-ol 138

hexan-1-ol CH3 – CH2 – CH2 – CH2 – CH2 – CH2 – OH 102

[3]

(b) Give two other characteristics of a homologous series.

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

..................................................................................................................................... [2]

(c) Draw a diagram showing the arrangement of the valency electrons in one molecule of the covalent compound methanol.

Use x to represent an electron from a carbon atom. Use o to represent an electron from an oxygen atom. Use ● to represent an electron from a hydrogen atom.

[3]

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(d) Alcohols can be oxidised to carboxylic acids by heating with acidic potassium manganate(VII).

(i) Draw the structural formula of the carboxylic acid formed by the oxidation ofpropan-1-ol. Show all the bonds.

[1]

(ii) Describe how ethanol could be oxidised to ethanoic acid by fermentation.

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

.............................................................................................................................. [2]

(e) Propan-1-ol and ethanoic acid react together to form an ester. Give its name and structural formula.

name ........................................................................................................................... [1]

formula

[1]

[Total: 13]

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7 Petrol is a mixture of hydrocarbons and additives. The combustion of petrol in car engines is a major source of air pollution. This is reduced by catalytic converters.

(a) Petrol is obtained from the gasoline fraction, boiling point range 40 °C to 100 °C, from the distillation of petroleum. Explain the term fraction.

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

..................................................................................................................................... [2]

(b) In many countries, a lead compound of the type Pb(C2H5)n used to be added to petrol to improve its combustion. After combustion, lead oxide was formed.

LEADED

98 OCTANE

(i) Octane is a constituent of petrol. Write the equation for the complete combustion of octane.

C8H18 + ...............O2 → ............... + ............... [2]

(ii) Dibromoethane was added to petrol to remove the lead oxide from inside the engine. Lead bromide was formed which escaped into the environment through the exhaust. Leaded petrol cannot be used with a catalytic converter. Give another reason why leaded petrol is no longer used.

.............................................................................................................................. [1]

(iii) What does each of the following tell you about the structure of dibromoethane?

dibromo ......................................................................................................................

eth ..............................................................................................................................

ane ....................................................................................................................... [2]

(iv) What additional information is needed to draw the structural formula ofdibromoethane?

.............................................................................................................................. [1]

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with 0.104 moles of C2H5 groups. What is the value of n? Show how you arrived at your answer.

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

..................................................................................................................................... [2]

(d) Some of the pollutants emitted by vehicle exhausts are carbon monoxide, oxides of nitrogen and unburnt hydrocarbons. Explain how the emission of these gases is reduced by a catalytic converter.

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

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

..................................................................................................................................... [3]

[Total: 13]

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34 A student is asked to draw a diagram showing the uses of limestone.

limestone

making

cement making lime

added, with hematite,

to a blast furnace

1 2

3

Which numbered lines show a correct use of limestone?

A 1 and 2 only

B 1 and 3 only

C 2 and 3 only

D 1, 2 and 3 35 Which structure is correctly named?

C C C

H

H

H

H

H

A

ethanoic acid

O

O H H C C

H

H H

H

B

ethene

H H C C

H

H H

H

C

ethanol

O H C C

H

H H

H

H

D

propane

C H

36 Which properties of the different compounds in petroleum enable its separation into fractions?

1 boiling point

2 chain length

3 chemical reactivity

4 solubility in water

A 1 and 2 B 1 and 3 C 2 and 4 D 3 and 4 37 Alkenes have the general formula CnH2n.

Which of the following is an alkene?

A CH2 B CH4 C C3H6 D C6H6

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38 Bitumen is a substance obtained from the fractional distillation of petroleum.

Which row describes its boiling point and the size of its molecules?

boiling point size of molecules

A high large

B high small

C low large

D low small

39 A hydrocarbon X is cracked to make Y and hydrogen.

Compound Z is formed by the addition polymerisation of Y.

To which homologous series do X, Y and Z belong?

alkane alkene

A X, Y and Z –

B X and Y Z

C X and Z Y

D Y and Z X

40 Which row is correct for ethanol?

burns made by

fermentation

A � �

B � �

C � �

D � �

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4 Silicon(IV) oxide, SiO2, and zirconium(IV) oxide, ZrO2, are both macromolecules. They have similar physical properties but silicon(IV) oxide is acidic and zirconium(IV) oxide

is amphoteric.

(a) Defi ne the term macromolecule.

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

..................................................................................................................................... [1]

(b) (i) Predict three physical properties of these two oxides.

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

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

.............................................................................................................................. [3]

(ii) Name an element which has the same physical properties as these two oxides.

.............................................................................................................................. [1]

(c) (i) Name a reagent that reacts with the oxides of both elements.

.............................................................................................................................. [1]

(ii) Name a reagent that reacts with only one of the oxides.

reagent ......................................................................................................................

oxide which reacts ............................................................................................... [2]

[Total: 8]

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3 Many organic compounds which contain a halogen have chloro, bromo or iodo in their name.

(a) The following diagram shows the structure of 1-chloropropane.

CH

H

H

C C

H

H

Cl

H

H

(i) Draw the structure of an isomer of this compound.

[1]

(ii) Describe how 1-chloropropane could be made from propane.

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

.............................................................................................................................. [2]

(iii) Suggest an explanation why the method you have described in (ii) does not produce a pure sample of 1-chloropropane.

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

.............................................................................................................................. [2]

(b) Organic halides react with water to form an alcohol and a halide ion.

CH3–CH2–I + H2O → CH3–CH2–OH + I –

(i) Describe how you could show that the reaction mixture contained an iodide ion.

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

.............................................................................................................................. [2]

(ii) Name the alcohol formed when 1-chloropropane reacts with water.

.............................................................................................................................. [1]

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(c) The speed (rate) of reaction between an organic halide and water can be measured by the following method.

A mixture of 10 cm3 of aqueous silver nitrate and 10 cm3 of ethanol is warmed to 60 °C. Drops of the organic halide are added and the time taken for a precipitate to form is measured.

Silver ions react with the halide ions to form a precipitate of the silver halide.

Ag+(aq) + X–(aq) → AgX(s)

Typical results for four experiments, A, B, C and D, are given in the table.

experiment organic halide number of drops time / min

A bromobutane 4 6

B bromobutane 8 3

C chlorobutane 4 80

D iodobutane 4 0.1

(i) Explain why it takes longer to produce a precipitate in experiment A than in B.

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

.............................................................................................................................. [2]

(ii) How does the order of reactivity of the organic halides compare with the order of reactivity of the halogens?

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

.............................................................................................................................. [2]

(iii) Explain why the time taken to produce a precipitate would increase if the experiments were repeated at 50 °C.

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

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

.............................................................................................................................. [3]

[Total: 15]

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7 The alcohols form a homologous series. The fi rst member of this series is methanol, CH3OH.

(a) (i) Give the general formula of the alcohols.

.............................................................................................................................. [1]

(ii) The mass of one mole of an alcohol is 116 g. What is its formula? Show your reasoning.

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

.............................................................................................................................. [2]

(iii) Draw a diagram showing the arrangement of the outer (valency) electrons in one molecule of methanol.

Use x to represent an electron from a carbon atom. Use o to represent an electron from a hydrogen atom. Use ● to represent an electron from an oxygen atom.

[3]

(b) Methanol is manufactured using the following method.

CH4(g) + H2O(g) → CO(g) + 3H2(g) reaction 1

CO(g) + 2H2(g) CH3OH(g) reaction 2

The conditions for reaction 2 are:

pressure 100 atmospheres catalyst a mixture of copper, zinc oxide and aluminium oxide temperature 250 °C

The forward reaction is exothermic.

(i) Why is high pressure used in reaction 2?

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

.............................................................................................................................. [2]

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(ii) Explain why using a catalyst at 250 °C is preferred to using a higher temperature of 350 °C and no catalyst.

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

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

.............................................................................................................................. [3]

(c) Methanol is oxidised by atmospheric oxygen. This reaction is catalysed by platinum.

(i) The products of this reaction include a carboxylic acid. Give its name and structural formula.

name .......................................................

structural formula showing all bonds

[2]

(ii) Deduce the name of the ester formed by the reaction of methanol with the carboxylic acid named in (i).

.............................................................................................................................. [1]

[Total: 14]

Combined Past Paper Questions on Organic Chemistry

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