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Practice paper written from an analysis of every
O-Level Chemistry paper, 2009–2026
Paper 1 Multiple Choice
FORECAST PAPER · SET 2 Medium
For practice before the 2026 examination
1 hour
Additional Materials: Paper for your answers, numbered 1 to 40
Write in soft pencil.
Do not use staples, paper clips, glue or correction fluid.
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 on a separate sheet of paper, numbered 1 to 40.
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 Periodic Table is printed on page 16.
The use of an approved scientific calculator is expected, where appropriate.
In a factory laboratory, magnesium is reacted with dilute sulfuric acid.
The volume of hydrogen given off is measured every 10 seconds.
Which pieces of apparatus are needed to measure the volume of hydrogen and the time?
Which statement describes fractional distillation?
A technician in an ink factory separates a black ink by paper chromatography.
Dyes R and S are known dyes.
The chromatogram is shown, with a scale in millimetres.
What is the Rf value of the dye in the ink that is the same as dye R?
A chemical plant makes a white solid, K.
A pure sample of K melts at 112 °C and boils at 305 °C.
Four samples, W, X, Y and Z, are taken from different batches and tested.
| sample | melting point / °C | boiling point / °C |
|---|---|---|
| W | 106–110 | 308–314 |
| X | 112 | 249 |
| Y | 109–112 | 305–308 |
| Z | 112 | 305 |
Which sample is pure K?
Four observations are made in a factory.
Which observations are evidence that particles in liquids and gases move?
Methane and chlorine escape from separate leaking pipes in a factory.
Which row describes the leak in which the gas diffuses fastest through the air?
| gas | temperature of the air / °C | |
|---|---|---|
| A | chlorine | 40 |
| B | chlorine | 20 |
| C | methane | 40 |
| D | methane | 20 |
Each diagram shows the particles in a sample of gas from a chemical plant.
Atoms of different elements are shown by different circles.
Which diagram shows a mixture of an element and a compound?
Urea is a fertiliser made in large quantities in chemical plants.
The diagram shows a molecule of urea.
What is the molecular formula of urea?
Iron powder is made in a factory by heating iron(III) oxide in a stream of hydrogen.
The equation for the reaction is shown.
16.0 g of iron(III) oxide is heated with excess hydrogen.
8.96 g of iron is obtained.
What is the percentage yield of iron?
In which mixture is the only reaction H+(aq) + OH−(aq) → H2O(l)?
Which row shows the products formed when aqueous sodium hydroxide, a base, reacts with dilute nitric acid and with warm aqueous ammonium nitrate?
| dilute nitric acid | warm aqueous ammonium nitrate | |
|---|---|---|
| A | sodium nitrate and hydrogen | no reaction |
| B | sodium nitrate and hydrogen | ammonia, sodium nitrate and water |
| C | sodium nitrate and water | no reaction |
| D | sodium nitrate and water | ammonia, sodium nitrate and water |
Crystals of copper(II) sulfate are made in a chemical works from copper(II) oxide and dilute sulfuric acid.
Three steps in the method are listed.
Which steps are correct?
Ammonia is manufactured from nitrogen and hydrogen.
Four statements about the sources of the two gases are listed.
Which statements are correct?
Ammonia is made by a reversible reaction between nitrogen and hydrogen.
A company tests four sets of conditions in a pilot plant.
The table shows the results.
| temperature / °C | pressure / atmospheres | catalyst | ammonia in the equilibrium mixture / % | time to reach equilibrium / min |
|---|---|---|---|---|
| 300 | 200 | iron | 67 | 600 |
| 450 | 200 | iron | 28 | 20 |
| 450 | 200 | none | 28 | 800 |
| 450 | 100 | iron | 17 | 30 |
Which statement is supported by the data?
A technician in a foundry has two unlabelled bottles.
One contains aqueous zinc nitrate and the other contains aqueous aluminium nitrate.
Which test distinguishes between the two solutions?
Which row describes a correct test for a gas?
| gas | test | observation | |
|---|---|---|---|
| A | ammonia | damp blue litmus paper | turns red |
| B | hydrogen | glowing splint | relights |
| C | oxygen | lighted splint | burns with a squeaky pop |
| D | sulfur dioxide | acidified potassium manganate(VII) | turns from purple to colourless |
Sodium chlorate(I), an oxidising agent used to bleach cloth, is added to aqueous potassium iodide.
Iron(II) sulfate, a reducing agent used to treat waste water, is added to acidified potassium manganate(VII).
Which row shows the colour changes?
| aqueous potassium iodide | acidified potassium manganate(VII) | |
|---|---|---|
| A | brown to colourless | purple to colourless |
| B | brown to colourless | colourless to purple |
| C | colourless to brown | purple to colourless |
| D | colourless to brown | colourless to purple |
Solid X is used in a ceramics factory.
Which statement explains these results?
Molten magnesium chloride is electrolysed using inert electrodes P and Q.
Which row shows the products formed at P and at Q?
| product at P | product at Q | |
|---|---|---|
| A | chlorine | magnesium |
| B | hydrogen | chlorine |
| C | magnesium | chlorine |
| D | magnesium | oxygen |
Which statement explains why elements in the same group of the Periodic Table have similar chemical properties?
Elements W, X, Y and Z have electronic configurations 2,5; 2,8,1; 2,8,6 and 2,8,8,2 respectively.
The letters are not the chemical symbols.
Which two elements are metals?
Argon is used to fill some electric light bulbs.
Which row describes argon and gives a reason for this use?
| particles in argon gas | reason for using argon | |
|---|---|---|
| A | single atoms | it does not react with the hot filament |
| B | single atoms | it reacts with the oxygen inside the bulb |
| C | molecules of two atoms | it does not react with the hot filament |
| D | molecules of two atoms | it reacts with the oxygen inside the bulb |
Platinum is used as a catalyst in the manufacture of nitric acid.
Vanadium(V) oxide is used as a catalyst in the manufacture of sulfuric acid.
Which compound is also most likely to be used as a catalyst in industry?
Scrap zinc is added to waste aqueous copper(II) sulfate from a factory.
Copper is deposited and the blue colour of the solution fades.
Which row describes the reaction?
| metal that forms positive ions more easily | ions that gain electrons | |
|---|---|---|
| A | copper | Cu2+ |
| B | copper | Zn2+ |
| C | zinc | Cu2+ |
| D | zinc | Zn2+ |
Samples of four metal carbonates are heated strongly under the same conditions.
What is the order of increasing thermal stability of the carbonates?
A manufacturer tests the rusting of iron nails.
An iron nail is placed in each of four tubes and the tubes are left for one week.
In which tubes does the nail not rust?
Hydrogen reacts with chlorine in the manufacture of hydrogen chloride.
The reaction releases energy to the surroundings.
Which statement explains this?
A company changes its lorries from diesel, a fossil fuel, to biodiesel, a biofuel made from vegetable oil.
Four statements about biodiesel are listed.
Which statements explain why biodiesel can be more environmentally sustainable than diesel in terms of carbon dioxide emission?
Which row describes the members of a homologous series?
| general formula | chemical properties | physical properties, e.g. boiling point | |
|---|---|---|---|
| A | different | similar | change gradually |
| B | the same | different | change gradually |
| C | the same | similar | are identical |
| D | the same | similar | change gradually |
An alkene made in a refinery has a relative molecular mass of 70.
What is the molecular formula of the alkene?
What is meant by the term polyunsaturated when it is used to describe a cooking oil?
Which formula represents an alcohol?
Which compound is a carboxylic acid?
In a vinegar factory, ethanol in wine is changed into ethanoic acid when air is blown through the wine.
Which statement about this change is correct?
Which pair of compounds reacts to form the ester ethyl butanoate?
A factory makes poly(ethene) by the addition polymerisation of ethene.
The relative molecular mass of one molecule of the polymer is 56 000.
How many ethene molecules join together to make one molecule of the polymer?
Part of the structure of a polymer is shown.
The hatched and open rectangles each represent part of a molecule.
Which row describes the polymer?
| type of polymerisation | name of polymer | |
|---|---|---|
| A | addition | nylon |
| B | addition | Terylene |
| C | condensation | nylon |
| D | condensation | Terylene |
Part of the structure of a polyester is shown.
Waste polyester fibres from a clothing factory are broken down into their monomers by heating with dilute sulfuric acid.
Three statements about this process are listed.
Which statements are correct?
Four statements are made about the sources of air pollutants.
Which statements are correct?
Which row describes the ozone layer and the main cause of its depletion?
| function of the ozone layer | main cause of its depletion | |
|---|---|---|
| A | absorbs infrared radiation from the Earth | carbon dioxide |
| B | absorbs infrared radiation from the Earth | chlorofluorocarbons |
| C | absorbs ultraviolet radiation from the Sun | carbon dioxide |
| D | absorbs ultraviolet radiation from the Sun | chlorofluorocarbons |
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