Cambridge O Level

CHEMISTRY 5070/11
Paper 1 Multiple Choice May/June 2021
1 hour

You must answer on the multiple choice answer sheet.

*9190527622*

You will need: Multiple choice answer sheet

Soft clean eraser
Soft pencil (type B or HB is recommended)

INSTRUCTIONS
 There are forty questions on this paper. Answer all questions.
 For each question there are four possible answers A, B, C and D. Choose the one you consider correct
and record your choice in soft pencil on the multiple choice answer sheet.
 Follow the instructions on the multiple choice answer sheet.
 Write in soft pencil.
 Write your name, centre number and candidate number on the multiple choice answer sheet in the
spaces provided unless this has been done for you.
 Do not use correction fluid.
 Do not write on any bar codes.
 You may use a calculator.

INFORMATION
 The total mark for this paper is 40.
 Each correct answer will score one mark.
 Any rough working should be done on this question paper.
 The Periodic Table is printed in the question paper.

This document has 16 pages.

IB21 06_5070_11/4RP
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1 A student has to measure 28.2 cm3 of aqueous sodium bromide.

Which piece of apparatus should the student select?

A B C D

2 Which property of a liquid ester can be used to check its purity before use as a food flavouring?

A boiling point
B colour
C smell
D solubility in water

3 Which sequence of procedures is used to separate a pure, dry sample of hydrated

copper(II) sulfate, CuSO4•5H2O, from a mixture containing hydrated copper(II) sulfate and
calcium carbonate, CaCO3?

A dissolve in water  distillation  crystallisation

B dissolve in water  filtration  crystallisation

C distillation  crystallisation  heating to remove all water

D fractional distillation  filtration  heating to remove all water

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4 J is an aqueous solution.

On addition of aqueous sodium hydroxide to J a green precipitate is formed.

The resulting mixture is heated and no gas is formed.

Aluminium foil is added to the warmed mixture. A gas is formed that turns damp red litmus paper
blue.

Which ions could be present in J?

A Fe3+ and NH4+

B Fe3+ and NO3–
C Fe2+ and NH4+
D Fe2+ and NO3–

5 Gas X has the following properties.

1 colourless
2 no effect on either damp red or blue litmus papers
3 no effect on limewater
4 flammable

What is gas X?

A ammonia
B chlorine
C hydrogen
D oxygen

6 Which particle contains most electrons?

A O3– B Ne C Na– D Mg3+

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7 The diagrams show the structures of two solids, P and Q.

P Q

Which row is correct?

has covalent conducts

bonding electricity

A P only P only
B P only Q only
C both P and Q P only
D both P and Q Q only

8 What is a covalent bond?

A a pair of electrons shared by two non-metallic atoms

B electrons being shared by a lattice of positively charged ions
C elements losing electrons to achieve a noble gas structure
D oppositely charged particles strongly attracting each other

9 The empirical formula of compound X is CH2 and the relative molecular mass, Mr, of X is 70.

What is the molecular formula of X?

A CH2 B C2H4 C C5H10 D CnH2n

10 A chemist wants to make calcium nitrate. They start with 8.00 g of pure calcium oxide and an
excess of dilute nitric acid. They produce 12.65 g of pure, dry anhydrous calcium nitrate crystals.

What is the percentage yield of calcium nitrate?

[relative atomic masses, Ar: Ca, 40; N, 14; H, 1; O, 16]

A 54.0 B 63.2 C 67.1 D 86.8

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11 The relative formula masses of four compounds are given.

A student has a 1.0 g sample of each compound.

Which sample contains the highest number of moles of oxygen atoms?

relative
compound
formula mass

A Al 2O3 102
B CuO 80
C H2SO4 98
D HNO3 63

12 How many elements combine to form the compound ammonium sulfate?

A 2 B 4 C 10 D 15

13 An aqueous mixture of copper(II) nitrate and silver nitrate is electrolysed with pure copper
electrodes.

Which half-equation correctly describes the change occurring at the anode?

A Cu  Cu2+ + 2e–

B Cu2+ + 2e–  Cu

C Ag  Ag+ + e–

D Ag+ + e–  Ag

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14 The diagram shows the electrolysis of concentrated and dilute aqueous sodium chloride using
inert electrodes. Gases are produced and collected in each of the test-tubes W, X, Y and Z.

W X Y Z

concentrated dilute
aqueous aqueous
sodium chloride sodium chloride

Which statements are correct?

1 Approximately equal volumes of gas are produced and collected in test-tubes W

and X.
2 Approximately equal volumes of gas are produced and collected in test-tubes Y
and Z.
3 Three different gases are produced in the experiment.

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

15 Which positive ions are present in aqueous copper(II) sulfate?

A copper(II) ions only

B copper(II) ions and hydrogen ions

C sulfate ions only

D sulfate ions and hydroxide ions

16 These statements refer to hydrogen and its use as a fuel.

1 Both water and hydrocarbons can be used as a source of hydrogen.

2 In a fuel cell hydrogen reacts with oxygen to generate electricity.
3 The reaction taking place in a fuel cell is a redox reaction.

Which statements are correct?

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

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17 Ethanol is produced by the fermentation of glucose from sugar cane. In some countries ethanol is
used as a fuel.

Which statements are correct?

1 Sugar cane is a non-renewable (finite) resource.

2 When sugar cane is growing it removes carbon dioxide from the atmosphere.

A 1 only
B 2 only
C both 1 and 2
D neither 1 nor 2

18 Which changes will speed up a chemical reaction?

1 decreasing the pressure in a reaction between gases

2 increasing the size of the solid particles in a reaction involving solids
3 increasing the temperature of any reaction
4 increasing the concentration of a solution

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

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19 Magnesium reacts with dilute sulfuric acid.

Mg(s) + H2SO4(aq)  MgSO4(aq) + H2(g)

Two experiments are carried out at 25 C.

experiment 1 24.0 g of powdered magnesium is reacted with 100 cm3 of 1.0 mol / dm3
sulfuric acid.
experiment 2 24.0 g of powdered magnesium is reacted with 50 cm3 of 2.0 mol / dm3
sulfuric acid.

During each experiment the volume of hydrogen produced is measured. The results are plotted
on a graph.

Which graph is correct?

A B

volume of volume of key

hydrogen hydrogen
experiment 1
produced produced
experiment 2

0 0
0 time 0 time

C D

volume of volume of
hydrogen hydrogen
produced produced

0 0
0 time 0 time

20 In which equations is the change in the underlined species correct?

oxidation
1 CH4 + 2O2 o CO2 + 2H2O

reduction
2 2H2S + SO2 o 3S + 2H2O

reduction
3 BrO3– + 5Br – + 6H+ o 3Br2 + 3H2O

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

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21 The Haber process converts nitrogen and hydrogen into ammonia.

N2(g) + 3H2(g) 2NH3(g)

Which row is correct?

change in condition position of equilibrium

A pressure is increased moves to the left

B pressure is reduced no change
C catalyst present moves to the right
D catalyst present no change

22 Which row shows the pH values for 0.1 mol / dm3 solutions of ammonia, hydrochloric acid,
sodium chloride and sodium hydroxide?

pH values
NH3 HCl NaCl NaOH

A 1 7 13 11
B 7 1 11 13
C 11 1 7 13
D 13 11 7 1

23 The water in a lake is acidic and the fish are dying. The water in the lake needs to be neutralised.

Which compound can be added in excess to neutralise the water in the lake?

A calcium carbonate
B phosphoric acid
C potassium hydroxide
D sodium nitrate

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24 Two incomplete statements about the preparation of an insoluble salt are given.

......1...... can be used to prepare insoluble salts, such as ......2...... .

The salt is collected by ...... 3...... and it is then ......4...... .

Which words correctly complete gaps 1–4?

1 2 3 4

A precipitation barium nitrate filtration evaporated

B precipitation lead sulfate evaporation washed and dried
C precipitation lead sulfate filtration washed and dried
D titration barium nitrate evaporation washed and dried

25 The Haber process is used to make ammonia at a temperature of 400 C and a pressure of
20 000 kPa. The temperature is changed to 500 C but the pressure is kept the same.

What will be the effects of this change on the production of ammonia?

A It is made at an increased rate and the position of the equilibrium moves to the left.
B It is made at an increased rate and the position of the equilibrium moves to the right.
C It is made at a decreased rate and the position of the equilibrium moves to the left.
D It is made at a decreased rate and the position of the equilibrium moves to the right.

26 Some properties which indicate the differences in elements are listed.

1 metallic character
2 number of electron shells in an atom
3 number of protons in an atom
4 total number of electrons in an atom

Which two properties increase across a period of the Periodic Table?

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

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27 Elements X and Y combine to form an ionic compound.

Atoms of X have more protons than atoms of Y.

Atoms of Y have more valence electrons than atoms of X.

Which statement is correct?

A Ions of X are negatively charged.

B Atoms of X have more electron shells than atoms of Y.
C X and Y are in the same period of the Periodic Table.
D X and Y are in the same group of the Periodic Table.

28 The elements in Group I of the Periodic Table show trends in both their reactivities and their
melting points. Rubidium is in Group I.

Which statement about rubidium is correct?

A It has a higher melting point than potassium.

B It reacts with water to produce an acidic solution.
C It reacts with water to produce oxygen gas.
D It is more reactive than potassium.

29 The properties of four substances are shown.

Which substance is a metal?

A It conducts electricity when dissolved in water but not when solid.

B It has a high melting point and conducts heat when solid.
C It has a low melting point and is brittle.
D It has a giant covalent structure with a high melting point.

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30 Group I elements and transition elements are metals.

Student X suggests that the Group I elements are above hydrogen in the metal reactivity series
but that not all transition elements are.

Student Y suggests that the densities of Group I elements are lower than those of the transition
elements.

Which students are correct?

A both X and Y
B X only
C Y only
D neither X nor Y

31 Tin is more reactive than lead but less reactive than iron.

Which method would be most suitable for extracting tin from its ore?

A electrolysis
B heating alone
C heating with carbon
D reacting with hydrogen

32 Attaching pieces of magnesium to underground iron pipes can protect the iron from corrosion.

Which reaction protects the iron from corrosion?

A Fe2+(aq) + 2e–  Fe(s)

B Fe(s)  Fe2+(aq) + 2e–

C Mg2+(aq) + 2e–  Mg(s)

D Mg(s)  Mg2+(aq) + 2e–

33 Which reactions take place during the extraction of aluminium from aluminium oxide using carbon
electrodes?

1 2O2–  O2 + 4e–

2 C + O2  CO2

3 Al 2+ + 2e–  Al

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

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34 Which statement about gases in the atmosphere is correct?

A Carbon monoxide is a pollutant which causes acid rain.

B Catalytic converters reduce carbon monoxide to carbon dioxide.
C Methane in the atmosphere depletes the ozone layer.
D Photosynthesis adds oxygen to the atmosphere.

35 How many moles of hydrogen chloride are formed when one mole of methane reacts with a large
excess of chlorine in sunlight?

A 1 B 2 C 3 D 4

36 Compound X is shown in the dot-and-cross diagram.

H H

C C C H

H H H

Which statement about compound X is correct?

A It is a saturated hydrocarbon.
B It is an isomer of butene.
C It will decolourise bromine water.
D Its name is propane.

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37 Which statements about alcohols are correct?

1 All alcohols contain the hydroxide ion, OH–.

2 Ethanol can be formed from ethene using a reaction catalysed by yeast.
3 Methanol can be oxidised to methanoic acid.
4 The alcohols X and Y shown are isomers.

X Y

H H H H H H H H

H C C C C H H C C C C H

H O H H H H H O

H H

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

38 An ester has the formula C2H5COOC2H5.

Which pair of compounds would react together to form this ester?

A ethanoic acid and ethanol

B ethanol and propanoic acid
C propanoic acid and propanol
D propanol and ethanoic acid

39 Which statement about polymers is correct?

A Nylon and Terylene are both polyesters.

B Proteins and nylon have the same monomer units.
C Proteins have the same amide linkages as nylon.
D Terylene and fats are esters but with different linkages.

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40 X is a polymer.

When X is hydrolysed one of the products is substance Y.

NH2

CH3 C COOH

H
Y

Which type of polymer is X?

A a complex carbohydrate
B a fat
C a protein
D an addition polymer

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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.

To avoid the issue of disclosure of answer-related information to candidates, all copyright acknowledgements are reproduced online in the Cambridge
Assessment International Education Copyright Acknowledgements Booklet. This is produced for each series of examinations and is freely available to download
at www.cambridgeinternational.org after the live examination series.

Cambridge Assessment International Education is part of the Cambridge Assessment Group. Cambridge Assessment is the brand name of the University of
Cambridge Local Examinations Syndicate (UCLES), which itself is a department of the University of Cambridge.

© UCLES 2021 5070/11/M/J/21

 The Periodic Table of Elements
Group

© UCLES 2021
I II III IV V VI VII VIII
1 2
H He
hydrogen helium
Key 1 4
3 4 atomic number 5 6 7 8 9 10

Li Be atomic symbol B C N O F Ne
lithium beryllium name boron carbon nitrogen oxygen fluorine neon
7 9 relative atomic mass 11 12 14 16 19 20
11 12 13 14 15 16 17 18
Na Mg Al Si P S Cl Ar
sodium magnesium aluminium silicon phosphorus sulfur chlorine argon
23 24 27 28 31 32 35.5 40
19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36
K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr
potassium calcium scandium titanium vanadium chromium manganese iron cobalt nickel copper zinc gallium germanium arsenic selenium bromine krypton
39 40 45 48 51 52 55 56 59 59 64 65 70 73 75 79 80 84
37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54
Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe
rubidium strontium yttrium zirconium niobium molybdenum technetium ruthenium rhodium palladium silver cadmium indium tin antimony tellurium iodine xenon
16

85 88 89 91 93 96 – 101 103 106 108 112 115 119 122 128 127 131
55 56 57–71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86

5070/11/M/J/21
lanthanoids
Cs Ba Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn
caesium barium hafnium tantalum tungsten rhenium osmium iridium platinum gold mercury thallium lead bismuth polonium astatine radon
133 137 178 181 184 186 190 192 195 197 201 204 207 209 – – –
87 88 89–103 104 105 106 107 108 109 110 111 112 114 116
actinoids
Fr Ra Rf Db Sg Bh Hs Mt Ds Rg Cn Fl Lv
francium radium rutherfordium dubnium seaborgium bohrium hassium meitnerium darmstadtium roentgenium copernicium flerovium livermorium
– – – – – – – – – – – – –

57 58 59 60 61 62 63 64 65 66 67 68 69 70 71
lanthanoids La Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu
lanthanum cerium praseodymium neodymium promethium samarium europium gadolinium terbium dysprosium holmium erbium thulium ytterbium lutetium
139 140 141 144 – 150 152 157 159 163 165 167 169 173 175
89 90 91 92 93 94 95 96 97 98 99 100 101 102 103
actinoids Ac Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No Lr
actinium thorium protactinium uranium neptunium plutonium americium curium berkelium californium einsteinium fermium mendelevium nobelium lawrencium
– 232 231 238 – – – – – – – – – – –

The volume of one mole of any gas is 24 dm3 at room temperature and pressure (r.t.p.).