Cambridge A Level Chemistry 9701 — 2020 Oct/Nov Paper 1 · Variant 2
9701/12/O/N/20 · 40 questions · 40 marks · ≈45 min
The question paper and its mark scheme, free to read here and free to download. This is Cambridge’s own paper, exactly as it was sat.
Question paper16 pages
















Mark scheme3 pages
Answers below. Sit the paper first if you are practising.



Questions as text
Q1 · What is the average oxidation number of sulfur in each compound?
1 What is the average oxidation number of sulfur in each compound? Ca(HSO3)2 Na2S2O3 A 4 2 B 4 4 C 6 2 D 6 4
Mark scheme: A
Q2 · An ore of manganese contains 4% by mass of MnO2 and no other manganese compound
2 An ore of manganese contains 4% by mass of MnO2 and no other manganese compound. Which mass of manganese would be obtained from 1 tonne of this ore? A 25.3 kg B 40.0 kg C 63.3 kg D 632 kg
Mark scheme: A
More questions on Reacting masses and volumes (of solutions and gases)
Q3 · Which atomic orbitals are occupied in an atom of phosphorus?
3 Which atomic orbitals are occupied in an atom of phosphorus? A 1p 2s 2p B 2s 2p 2d C 2s 2p 3s D 2p 3s 3d
Mark scheme: C
More questions on Electrons, energy levels and atomic orbitals
Q4 · The structure of compound A is shown
4 The structure of compound A is shown. compound A CH3 CH3 CH CH C CH C CH CH2OH CH3 CH3 Some of the carbon atoms in compound A have a tetrahedral arrangement of bonds. Some of the carbon atoms in compound A have a trigonal planar arrangement of bonds. How many carbon atoms are there of each type? tetrahedral trigonal planar A 5 12 B 8 8 C 9 6 D 9 8
Mark scheme: D
More questions on Shapes of organic molecules; σ and π bonds
Q5 · A white powder is known to be a mixture of magnesium oxide and aluminium oxide
5 A white powder is known to be a mixture of magnesium oxide and aluminium oxide. 100 cm3 of 2 mol dm–3 NaOH(aq) is just enough to dissolve the aluminium oxide in x grams of the mixture. The reaction is shown. Al 2O3 + 2OH– + 3H2O → 2Al (OH)4 – 800 cm3 of 2 mol dm–3 HCl (aq) is just enough to dissolve all of the oxide in x grams of the mixture. The reactions are shown. Al 2O3 + 6H+ → 2Al 3+ + 3H2O MgO + 2H+ → Mg2+ + H2O How many moles of each oxide are present in x grams of the mixture? aluminium magnesium oxide oxide A 0.05 0.25 B 0.05 0.50 C 0.10 0.25 D 0.10 0.50
Mark scheme: D
More questions on Reacting masses and volumes (of solutions and gases)
Q6 · A graph of pV against T is shown for a fixed mass of gas
6 A graph of pV against T is shown for a fixed mass of gas. (p = pressure, V = volume and T = temperature in K.) pV T Which gas gives this graph over the widest range of temperatures and pressures? A hydrogen, H2 B hydrogen chloride, HCl C hydrogen fluoride, HF D oxygen, O2
Mark scheme: A
More questions on The gaseous state: ideal and real gases and pV = nRT
Q7 · A weather balloon is filled with 12.0 kg helium
7 A weather balloon is filled with 12.0 kg helium. The weather balloon reaches a height of 20 km, the pressure inside the balloon is 6000 Pa and the temperature is 216 K. What is the volume of the weather balloon at this height, correct to three significant figures? A 897 dm3 B 1790 dm3 C 897 000 dm3 D 1 790 000 dm3
Mark scheme: C
More questions on The gaseous state: ideal and real gases and pV = nRT
Q8 · Which pair of enthalpy changes will always share the same sign (i.e
8 Which pair of enthalpy changes will always share the same sign (i.e. both are always exothermic or both are always endothermic)? A enthalpy change of atomisation and enthalpy change of neutralisation B enthalpy change of atomisation and enthalpy change of solution C enthalpy change of combustion and enthalpy change of hydration D enthalpy change of solution and enthalpy change of hydration
Mark scheme: C
Q9 · Chlorine dioxide, Cl O2, reacts with sodium hydroxide in the reaction shown
9 Chlorine dioxide, Cl O2, reacts with sodium hydroxide in the reaction shown. 2Cl O2 + 2OH– → Cl O2 – + Cl O3 – + H2O Which statement correctly describes this redox reaction? A Chlorine atoms are oxidised and oxygen atoms are reduced. B Chlorine atoms are reduced and oxygen atoms are oxidised. C Some chlorine atoms are oxidised and some chlorine atoms are reduced. D Some oxygen atoms are oxidised and some oxygen atoms are reduced.
Mark scheme: C
Q10 · Sulfur dioxide and oxygen react to form sulfur trioxide
10 Sulfur dioxide and oxygen react to form sulfur trioxide. The reaction is reversible. 2SO2(g) + O2(g) 2SO3(g) Kp = 2.96 × 10–9 Pa–1 at 700 °C The reaction is allowed to reach equilibrium at 700 °C. The partial pressure of O2(g) is 375 kPa and the partial pressure of SO3(g) is 20.3 kPa. What is the partial pressure of SO2(g)? A 19.3 kPa B 609 kPa C 18 300 kPa D 609 000 kPa
Mark scheme: B
More questions on Chemical equilibria: reversible reactions, dynamic equilibrium
Q11 · Ammonia is made by the Haber process
11 Ammonia is made by the Haber process. The reactants are nitrogen and hydrogen. N2(g) + 3H2(g) 2NH3(g) ∆H is negative What will increase the rate of the forward reaction? A adding argon to the mixture but keeping the total volume constant B decreasing the temperature C increasing the total pressure by reducing the total volume at constant temperature D removing ammonia as it is made but keeping the total volume of the mixture the same
Mark scheme: C
More questions on Effect of temperature on reaction rates and the concept of activation energy
Q12 · Element X, in Period 3, has the following properties
12 Element X, in Period 3, has the following properties. ● Its oxide has a giant structure. ● It forms covalent bonds with chlorine. ● Its oxide will neutralise HCl (aq). What is element X? A Mg B Al C Si D P
Mark scheme: B
More questions on Periodicity of chemical properties of the elements in Period 3
Q13 · Which row could refer to barium metal and barium hydroxide?
13 Which row could refer to barium metal and barium hydroxide? colour seen pH of a saturated when the metal solution of is burnt in O2 the hydroxide A green flame 8 B green flame 13 C white flame 8 D white flame 13
Mark scheme: B
Q14 · AgNO3(aq) is added to a solution of a halide ion, X–(aq), and aqueous ammonia is then…
14 AgNO3(aq) is added to a solution of a halide ion, X–(aq), and aqueous ammonia is then added. The ionic equations for the two reactions that occur are shown. Ag+(aq) + X–(aq) AgX(s) equilibrium 1 Ag+(aq) + 2NH3(aq) Ag(NH3)2 +(aq) equilibrium 2 Which statement is correct? A The position of equilibrium 1 lies to the left when X– = I–. B Increasing the concentration of ammonia causes the position of equilibrium 1 to move to the left. C Kc for equilibrium 2 is larger when X– = Cl – than when X– = I–. D Equilibrium 2 is a redox reaction.
Mark scheme: B
Q15 · Water and ammonia take part in a reaction that produces the ammonium ion
15 Water and ammonia take part in a reaction that produces the ammonium ion. Which statement about this reaction is correct? A The ammonia molecule and the ammonium ion do not have dipole moments. B The bond angle changes from 109.5° in the ammonia molecule to 107° in the ammonium ion. C The reaction is a redox reaction. D The water is acting as an acid.
Mark scheme: D
Q16 · Due to their similar ionic radii, the reactions of lithium and magnesium and their…
16 Due to their similar ionic radii, the reactions of lithium and magnesium and their corresponding compounds are very similar. Which statement about the reactions of lithium or its compounds can be predicted from this statement? A Lithium burns very slowly in oxygen. B Lithium carbonate decomposes on heating in a blue Bunsen burner flame, forming lithium oxide and carbon dioxide. C Lithium nitrate decomposes on heating, forming lithium nitrite, LiNO2, and oxygen. D Lithium reacts very violently with cold water, producing hydrogen.
Mark scheme: B
Q17 · Which statement about Group 17 elements and their compounds is correct?
17 Which statement about Group 17 elements and their compounds is correct? A Chlorine reacts with cold concentrated sodium hydroxide to form NaCl and NaCl O3. B HCl is more thermally stable than HBr because chlorine is less electronegative than bromine. C Iodide ions are oxidised to iodine by concentrated sulfuric acid. D Silver iodide is soluble in dilute aqueous ammonia.
Mark scheme: C
More questions on The chemical properties of the halogen elements and the hydrogen halides
Q18 · Which substance, when warmed with aqueous ammonium chloride, would produce an alkaline…
18 Which substance, when warmed with aqueous ammonium chloride, would produce an alkaline gas? A CH3CO2H B CH3CH2OH C CH3CO2CH3 D CH3CH2ONa
Mark scheme: D
Q19 · Compound X is the oxide of a Period 3 element
19 Compound X is the oxide of a Period 3 element. Compound X reacts with water to give an acidic solution. A solution is prepared by reacting 0.100 g of compound X with an excess of water. This solution is neutralised by exactly 25.0 cm3 of 0.100 mol dm–3 sodium hydroxide solution. What could be the identity of compound X? A Al 2O3 B MgO C P4O10 D SO3
Mark scheme: D
More questions on Periodicity of chemical properties of the elements in Period 3
Q20 · The unsaturated hydrocarbon octa-1,3,5,7-tetraene, C8H10, can display geometric isomerism
20 The unsaturated hydrocarbon octa-1,3,5,7-tetraene, C8H10, can display geometric isomerism. octa-1,3,5,7-tetraene CH2=CHCH=CHCH=CHCH=CH2 How many isomers exist? A 2 B 3 C 4 D 8
Mark scheme: B
More questions on Isomerism: structural isomerism and stereoisomerism
Q21 · What is the correct name for the compound shown?
21 What is the correct name for the compound shown? HO A 1,2,2-trimethylbutan-3-ol B 2-ethyl-2-methylbutan-2-ol C 3,3-dimethylpentan-2-ol D 4-hydroxy-3,3-dimethylpentane
Mark scheme: C
More questions on Formulas, functional groups and the naming of organic compounds
Q22 · A polymer has the following repeat unit
22 A polymer has the following repeat unit. It is made from two different monomers. CH2 CHCl CH2 CH CH CH2 Which pair of monomers could be used to make this polymer? A CH2=CHCl and CH2=CH2 B CH2=CHCl and CH2=CH–CH=CH2 C CH3–CH2Cl and CH3–CH=CH–CH3 D CH3–CH=CH–CH3 and CH2=CHCl
Mark scheme: B
Q23 · Compound X contains two functional groups
23 Compound X contains two functional groups. compound X O CH3 C CHO Which reagent will react with only one of the functional groups? A acidified potassium dichromate(VI) B 2,4-DNPH reagent C hydrogen cyanide D NaBH4
Mark scheme: A
Q24 · Ethanol can be converted into ethene in a single reaction
24 Ethanol can be converted into ethene in a single reaction. Ethanol can be converted into bromoethane in a single reaction. Under standard laboratory conditions, is a catalyst used in these reactions? ethanol to ethene ethanol to bromoethane A yes yes B yes no C no yes D no no
Mark scheme: B
Q25 · Diols in which both hydroxy groups are bonded to the same carbon atom can spontaneously…
25 Diols in which both hydroxy groups are bonded to the same carbon atom can spontaneously eliminate a molecule of water to produce a carbonyl compound. Which compound, after complete hydrolysis, gives a silver mirror with Tollens’ reagent? A 1,1-dibromobutane B 1,2-dibromobutane C 1,3-dibromobutane D 2,2-dibromobutane
Mark scheme: A
Q26 · Which alcohol will give a yellow precipitate when warmed with alkaline aqueous iodine?
26 Which alcohol will give a yellow precipitate when warmed with alkaline aqueous iodine? A (CH3)2CHCH2OH B (CH3)3COH C CH3CH2C(OH)(CH3)2 D CH3CH(OH)CH2CH3
Mark scheme: D
Q27 · How many structural isomers are there of molecular formula C5H10O that give a red…
27 How many structural isomers are there of molecular formula C5H10O that give a red precipitate with Fehling’s solution? A 1 B 2 C 3 D 4
Mark scheme: D
Q28 · Which statement about the use of alkane fuels in internal combustion engines is correct?
28 Which statement about the use of alkane fuels in internal combustion engines is correct? A C8H18 is used as fuel in internal combustion engines and reacts with oxygen and nitrogen from the air. B In limited oxygen, CO is produced which oxidises SO2 to SO3 in the atmosphere. C The catalytic converter removes polluting gases including NO2 and CO2. D Unburnt hydrocarbons and NO2 can react in sunlight to produce photochemical smog.
Mark scheme: D
Q29 · Compound Z is shown
29 Compound Z is shown. compound Z HO CO2H O HO O OH What is produced in good yield when compound Z is treated with an excess of sodium carbonate solution at room temperature? A B HO CO2Na NaO CO2Na O O HO O NaO O OH ONa C D NaO CO2H HO CO2Na O O + NaO O HO OH HO ONa OH
Mark scheme: A
Q30 · The infra-red spectrum shown was obtained from compound G
30 The infra-red spectrum shown was obtained from compound G. 100 transmittance / % 50 0 4000 3000 2000 1500 1000 500 wavenumber / cm–1 What could be compound G? A CH3COCH2OH B CH3CH2CO2H C CH3CO2CH3 D CH3CHCHCH3
Mark scheme: C
Q31 · The symbol for a phosphorus ion is 33 15P 3 −
31 The symbol for a phosphorus ion is 33 15P 3 − . The symbol for a potassium ion is 37 K + . 19 What do these two ions have in common? 1 the same number of electrons 2 the same number of neutrons 3 the same number of protons
Mark scheme: B
Q32 · The repeat unit of a polymer is shown
32 The repeat unit of a polymer is shown. H CN C C H CO2C2H5 n Which types of intermolecular forces exist in the solid polymer? 1 temporary dipole – induced dipole interactions 2 permanent dipole – permanent dipole interactions 3 hydrogen bonds
Mark scheme: B
More questions on Intermolecular forces, electronegativity and bond properties
Q33 · The diagram illustrates the enthalpy changes of a set of reactions
33 The diagram illustrates the enthalpy changes of a set of reactions. ∆H = –134 kJ mol–1 R S ∆H = +92 kJ mol–1 ∆H = –75 kJ mol–1 T U Which statements are correct? 1 The enthalpy change for the transformation U → R is + 42 kJ mol–1. 2 The enthalpy change for the transformation T → S is endothermic. 3 The enthalpy change for the transformation R → T is – 33 kJ mol–1.
Mark scheme: D
Q34 · Which statements about a reaction that has reached dynamic equilibrium are correct?
34 Which statements about a reaction that has reached dynamic equilibrium are correct? 1 The rate of the forward reaction equals the rate of the reverse reaction. 2 There is no overall change in the concentrations of reactants and products. 3 There is no change in the measurable properties of the system.
Mark scheme: A
More questions on Chemical equilibria: reversible reactions, dynamic equilibrium
Q35 · Group 2 elements and their compounds show trends in their physical and chemical properties
35 Group 2 elements and their compounds show trends in their physical and chemical properties. Barium is above radium in Group 2 of the Periodic Table. Which statements are likely to be correct? 1 Barium hydroxide is less soluble than radium hydroxide. 2 Barium reacts less vigorously with water than radium does. 3 Barium sulfate is more soluble than radium sulfate.
Mark scheme: A
Q36 · Which statements are correct?
36 Which statements are correct? 1 The empirical formula of silicon(IV) oxide is SiO2. 2 The molecular formula of phosphorus(V) oxide is P2O5. 3 Silicon(IV) oxide and phosphorus(V) oxide are both simple molecular compounds.
Mark scheme: D
Q37 · Which reagents could be used, under suitable conditions, to oxidise CH3CH2CH2OH to…
37 Which reagents could be used, under suitable conditions, to oxidise CH3CH2CH2OH to CH3CH2CHO? 1 acidified potassium manganate(VII) 2 acidified potassium dichromate(VI) 3 Tollens’ reagent
Mark scheme: B
Q38 · Which free radicals can be generated during a free-radical substitution reaction between…
38 Which free radicals can be generated during a free-radical substitution reaction between chlorine and ethane? 1 CH3• 2 CH2Cl CH2• 3 CH3CCl 2•
Mark scheme: C
Q39 · Which substances have molecular formula C4H8O?
39 Which substances have molecular formula C4H8O? 1 O 2 O OH 3
Mark scheme: A
More questions on Isomerism: structural isomerism and stereoisomerism
Q40 · Which reactions produce pentanoic acid?
40 Which reactions produce pentanoic acid? 1 CH3CH2CH2CH(OH)CH3 + H+ / MnO4 –(aq) 2 CH3OCO(CH2)3CH3 + HCl (aq) 3 CH3(CH2)3CN + H2SO4(aq)
Mark scheme: C
What was in this paper
The subtopics covered by these 40 questions, and how many questions each got. Open one in a new tab to see every Cambridge question on it.
3Aldehydes and ketones2Carboxylic acids2Chemical equilibria: reversible reactions, dynamic equilibrium2Isomerism: structural isomerism and stereoisomerism2Periodicity of chemical properties of the elements in Period 32Reacting masses and volumes (of solutions and gases)2Redox processes: electron transfer and changes in oxidation number (oxidation state)2The gaseous state: ideal and real gases and pV = nRT2Acids and bases1Addition polymerisation1Alcohols1Alcohols1Alkanes1Arenes1Bonding and structure1Effect of temperature on reaction rates and the concept of activation energy1Electrons, energy levels and atomic orbitals1Enthalpies of solution and hydration1Formulas, functional groups and the naming of organic compounds1Halogenoalkanes1Hess’s law1Infrared spectroscopy1Intermolecular forces, electronegativity and bond properties1Organic synthesis1Particles in the atom and atomic radius1Shapes of molecules1Shapes of organic molecules; σ and π bonds1Some reactions of the halide ions1The chemical properties of the halogen elements and the hydrogen halides1What you needed in this session
Cambridge’s own grade thresholds for 2020 Oct/Nov, Paper 1 · Variant 2. A higher threshold means an easier paper — the bar moves with how the cohort did.