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Practice paper written from an analysis of every
O-Level Science (Chemistry) paper, 2010–2026
Paper 1 Multiple Choice (Chemistry section)
FORECAST PAPER · SET 3 Medium
For practice before the 2026 examination
30 minutes
Additional Materials: Paper for your answers, numbered 1 to 20
Write in soft pencil.
Do not use staples, paper clips, glue or correction fluid.
There are twenty 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 on a separate sheet of paper, numbered 1 to 20.
Each correct answer will score one mark. A mark will not be deducted for a wrong answer.
Any rough working should be done in this booklet.
A copy of the Data Sheet is printed on page 11.
A copy of the Periodic Table is printed on page 12.
The use of an approved scientific calculator is expected, where appropriate.
A student makes hydrogen chloride gas in a flask.
Hydrogen chloride is very soluble in water and is denser than air.
The student wants to measure the volume of gas formed every 30 s.
Which apparatus should the student use?
A student wants to obtain each liquid from a mixture of two liquids that mix completely.
The boiling point of liquid J is 56 °C and the boiling point of liquid K is 97 °C.
Which row shows a suitable method and the liquid that is collected first?
| method | liquid collected first | |
|---|---|---|
| A | fractional distillation | K |
| B | fractional distillation | J |
| C | paper chromatography | K |
| D | paper chromatography | J |
The diagram shows the structure of an atom.
Which row shows the particles found at X and at Y?
| particles at X | particles at Y | |
|---|---|---|
| A | electrons only | protons and neutrons |
| B | neutrons and electrons | protons |
| C | protons and electrons | neutrons |
| D | protons and neutrons | electrons |
Magnesium burns in oxygen to form magnesium oxide, an ionic compound.
Each ‘dot-and-cross’ diagram shows only the outer shell electrons.
Electrons from magnesium atoms are shown as crosses and electrons from oxygen atoms as dots.
Which diagram shows the ions in magnesium oxide?
The sulfate of metal M has the formula M2(SO4)3, where the sulfate ion is SO42−.
The letter M is not the chemical symbol.
What is the formula of the oxide of M?
Which statement about one mole of water, H2O, is correct?
A student investigates the reactions of calcium hydroxide, a base.
Four statements about calcium hydroxide are made.
Which statements are correct?
A burning strip of magnesium is lowered into a gas jar of carbon dioxide.
The magnesium continues to burn and forms white magnesium oxide and black specks of carbon.
Which statement is correct?
Elements P and Q are in Period 3 of the Periodic Table.
The proton number of P is 12 and the proton number of Q is 16.
The letters are not the chemical symbols.
Which statement is correct?
Lithium, sodium and potassium are in Group 1.
A data book gives the melting points of lithium and potassium as 181 °C and 63 °C.
Which temperature could be the melting point of sodium?
Which diagram shows an atom of an unreactive element?
A student reacts excess magnesium with dilute sulfuric acid in two experiments, 1 and 2.
The volume and concentration of the acid are the same in both experiments.
The volume of hydrogen formed is measured every 20 s.
| time / s | volume of hydrogen in experiment 1 / cm3 | volume of hydrogen in experiment 2 / cm3 |
|---|---|---|
| 0 | 0 | 0 |
| 20 | 18 | 30 |
| 40 | 30 | 40 |
| 60 | 38 | 40 |
| 80 | 40 | 40 |
| 100 | 40 | 40 |
Which statement about the experiments is correct?
Crude oil is separated into fractions P, Q and R in a fractionating column.
Which statement is correct?
Which two types of reaction can methane undergo?
A large alkane is cracked and the gases formed are collected.
The gases turn aqueous bromine from orange to colourless.
A lighted splint held at the mouth of a gas jar of the gases gives a ‘pop’.
Which row shows two substances that must be present in the gases?
Which row describes a polyunsaturated cooking oil?
| number of carbon–carbon double bonds in each molecule | effect on aqueous bromine | |
|---|---|---|
| A | more than one | turns colourless |
| B | more than one | no change |
| C | only one | turns colourless |
| D | only one | no change |
A student wants to change ethanol into ethanoic acid.
Four methods are suggested.
Which methods will form ethanoic acid?
A student examines a plastic bag and a piece of clingfilm.
Both are made from poly(ethene).
Which row describes the properties of poly(ethene) that make it suitable for these uses?
| flexibility | solubility in water | |
|---|---|---|
| A | brittle | insoluble |
| B | brittle | soluble |
| C | flexible | insoluble |
| D | flexible | soluble |
Which list shows the four main gases in dry air in order of decreasing volume?
Electric sparks are passed through a sealed flask of dry air to model lightning.
Which air pollutant forms in the flask?
| aluminium hydroxide | white |
| calcium hydroxide | white |
| copper(II) hydroxide | light blue |
| iron(II) hydroxide | green |
| iron(III) hydroxide | red-brown |
| zinc hydroxide | white |
Group | |||||||||||||||||
1 | 2 |
| 13 | 14 | 15 | 16 | 17 | 18 | |||||||||
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| 1 H hydrogen 1 |
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| 2 He helium 4 | ||
3 Li lithium 7 | 4 Be beryllium 9 |
| proton (atomic) number atomic symbol name relative atomic mass |
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| 5 B boron 11 | 6 C carbon 12 | 7 N nitrogen 14 | 8 O oxygen 16 | 9 F fluorine 19 | 10 Ne neon 20 | ||
11 Na sodium 23 | 12 Mg magnesium 24 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 Al aluminium 27 | 14 Si silicon 28 | 15 P phosphorus 31 | 16 S sulfur 32 | 17 Cl chlorine 35.5 | 18 Ar argon 40 |
19 K potassium 39 | 20 Ca calcium 40 | 21 Sc scandium 45 | 22 Ti titanium 48 | 23 V vanadium 51 | 24 Cr chromium 52 | 25 Mn manganese 55 | 26 Fe iron 56 | 27 Co cobalt 59 | 28 Ni nickel 59 | 29 Cu copper 64 | 30 Zn zinc 65 | 31 Ga gallium 70 | 32 Ge germanium 73 | 33 As arsenic 75 | 34 Se selenium 79 | 35 Br bromine 80 | 36 Kr krypton 84 |
37 Rb rubidium 85 | 38 Sr strontium 88 | 39 Y yttrium 89 | 40 Zr zirconium 91 | 41 Nb niobium 93 | 42 Mo molybdenum 96 | 43 Tc technetium – | 44 Ru ruthenium 101 | 45 Rh rhodium 103 | 46 Pd palladium 106 | 47 Ag silver 108 | 48 Cd cadmium 112 | 49 In indium 115 | 50 Sn tin 119 | 51 Sb antimony 122 | 52 Te tellurium 128 | 53 I iodine 127 | 54 Xe xenon 131 |
55 Cs caesium 133 | 56 Ba barium 137 | 57–71 lanthanoids
| 72 Hf hafnium 178 | 73 Ta tantalum 181 | 74 W tungsten 184 | 75 Re rhenium 186 | 76 Os osmium 190 | 77 Ir iridium 192 | 78 Pt platinum 195 | 79 Au gold 197 | 80 Hg mercury 201 | 81 Tl thallium 204 | 82 Pb lead 207 | 83 Bi bismuth 209 | 84 Po polonium – | 85 At astatine – | 86 Rn radon – |
87 Fr francium – | 88 Ra radium – | 89–103 actinoids
| 104 Rf rutherfordium – | 105 Db dubnium – | 106 Sg seaborgium – | 107 Bh bohrium – | 108 Hs hassium – | 109 Mt meitnerium – | 110 Ds darmstadtium – | 111 Rg roentgenium – | 112 Cn copernicium – | 113 Nh nihonium – | 114 Fl flerovium – | 115 Mc moscovium – | 116 Lv livermorium – | 117 Ts tennessine – | 118 Og oganesson – |
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lanthanoids | 57 La lanthanum 139 | 58 Ce cerium 140 | 59 Pr praseodymium 141 | 60 Nd neodymium 144 | 61 Pm promethium – | 62 Sm samarium 150 | 63 Eu europium 152 | 64 Gd gadolinium 157 | 65 Tb terbium 159 | 66 Dy dysprosium 163 | 67 Ho holmium 165 | 68 Er erbium 167 | 69 Tm thulium 169 | 70 Yb ytterbium 173 | 71 Lu lutetium 175 |
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actinoids | 89 Ac actinium – | 90 Th thorium 232 | 91 Pa protactinium 231 | 92 U uranium 238 | 93 Np neptunium – | 94 Pu plutonium – | 95 Am americium – | 96 Cm curium – | 97 Bk berkelium – | 98 Cf californium – | 99 Es einsteinium – | 100 Fm fermium – | 101 Md mendelevium – | 102 No nobelium – | 103 Lr lawrencium – |
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The volume of one mole of any gas is 24 dm3 at room temperature and pressure (r.t.p.).
The Avogadro constant, L = 6.02 × 1023 mol-1