AS Level Chemistry Paper 2 · AS Structured Questions practice papers
AS · 60 marks · 1h 15m. Each generated paper follows the 9701 Paper 2 · AS Structured Questions format, with the same number and style of questions as the real exam, and comes with a Cambridge-style mark scheme.
MgO giant ionic lattice with strong electrostatic attractions B1 SiO₂ giant covalent with many strong covalent bonds B1
2
Question 2Structured · 7 marksA* challenge
Ethylamine can be made from bromoethane.
(a)
State the reagent and conditions.
[2]
(b)
Explain why excess ammonia is used.
[2]
(c)
Write an equation for ethylamine acting as a base with hydrochloric acid.
[1]
(d)
Explain why ethylamine is a stronger base than ammonia.
[2]
Show answers and mark scheme
Part
Answer and marking points
Marks
(a)
excess ethanolic ammonia, heat in sealed tube
excess NH₃ in ethanol B1 heat in a sealed tube (under pressure) B1
2
(b)
reduces further substitution
ethylamine is itself a nucleophile M1 excess NH₃ reduces formation of secondary/tertiary amines M1
2
(c)
C₂H₅NH₂ + HCl → C₂H₅NH₃⁺Cl⁻
C₂H₅NH₂ + HCl → C₂H₅NH₃⁺Cl⁻ B1
1
(d)
ethyl group electron-donating
ethyl group has a positive inductive effect M1 so the lone pair on N is more available to accept H⁺ M1
2
Question 3Structured · 3 marks
Chlorine reacts with sodium hydroxide.
Write the equation for the reaction with cold dilute NaOH and state the oxidation numbers of chlorine.
[3]
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Part
Answer and marking points
Marks
Cl₂ + 2NaOH → NaCl + NaClO + H₂O; 0, −1, +1
equation B1 0 → −1 and +1 B1 disproportionation B1
3
Question 4Structured · 3 marks
When 0.061 mol of a solid dissolves in 50 cm3 of water the temperature rises by 11 °C. Calculate the enthalpy change of solution in kJ mol−1. (c = 4.18 J g−1 K−1)
[3]
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Part
Answer and marking points
Marks
−37.7 kJ mol−1
q = mcΔT C1 ΔH = −q/n C1 −37.7 A1
3
Question 5Structured · 13 marks
This question is about rates of reaction.
(a)
Sketch the Boltzmann distribution of molecular energies for a gas at temperature T, and on the same axes the curve at a higher temperature. Label the activation energy, Ea.
Fig. 5.1
[3]
(b)
Use your sketch to explain why a small increase in temperature causes a large increase in the rate of reaction.
[2]
(c)
Explain, using the Boltzmann distribution, how a catalyst increases the rate of a reaction.
[2]
(d)
Distinguish between homogeneous and heterogeneous catalysis, giving one example of each.
[3]
(e)
Describe how the rate of the reaction between calcium carbonate and hydrochloric acid could be followed, and how the initial rate is found from the results.
[3]
Show answers and mark scheme
Part
Answer and marking points
Marks
(a)
skewed curve from origin; higher T: peak lower and to the right, same area; Ea marked
curve starting at the origin, peak, long tail not touching axis B1 higher-T curve with lower peak shifted to higher energy B1 same area under both curves and Ea marked B1
3
(b)
many more molecules with energy ≥ Ea; more successful collisions per unit time
the number of molecules with energy greater than or equal to Ea increases greatly (area beyond Ea) B1 so the frequency of successful collisions increases B1
2
(c)
alternative route with lower Ea; more molecules exceed it
provides an alternative reaction pathway with a lower activation energy B1 a greater proportion of molecules have energy above the new EaB1
2
(d)
same phase vs different phase; e.g. H⁺ in esterification / Fe in Haber
Any 3 of: homogeneous: catalyst in the same phase as reactants; heterogeneous: different phase; correct example of each (e.g. H₂SO₄ in esterification; Fe in Haber process / Pt in catalytic converter) B3
3
(e)
measure mass loss / gas volume against time; plot graph; gradient of tangent at t = 0
measure the loss in mass (or volume of CO₂) at regular time intervals B1 plot mass loss against time B1 draw a tangent at t = 0 and find its gradient B1
3
Question 6Structured · 9 marks
An organic compound X contains carbon, hydrogen and oxygen only. Its mass spectrum shows a molecular ion peak at m/e = 74 with an M+1 peak of relative height 3.3% of the M peak.
(a)
Explain the origin of the M+1 peak.
[1]
(b)
Use the M+1 peak to deduce the number of carbon atoms in a molecule of X.
[2]
(c)
The infrared spectrum of X shows a broad absorption at 2500–3000 cm−1 and a strong absorption at 1710 cm−1. Identify X and explain your reasoning.
[3]
(d)
X reacts with ethanol in the presence of concentrated sulfuric acid. Name the product and state how the IR spectrum of the product differs from that of X.
[3]
Show answers and mark scheme
Part
Answer and marking points
Marks
(a)
molecules containing one carbon-13 atom
molecules that contain one ¹³C atom (natural abundance 1.1%) B1
1
(b)
3
n = (M+1 height / M height) × 100/1.1 M1 3 A1
2
(c)
propanoic acid
broad O–H of a carboxylic acid B1 C=O at 1710 cm−1B1 propanoic acid, CH₃CH₂COOH B1
3
(d)
ethyl ester; no broad O–H; C=O and C–O remain
ethyl propanoate B1 the broad O–H absorption disappears B1 C=O (~1740) and C–O (~1200) absorptions remain B1
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Original Cambridge-style practice questions written for mentorriyaz.in. These are not Cambridge past paper questions, and this site is not affiliated with or endorsed by Cambridge University Press & Assessment. Updated 2026-11-04. Paper generator · mentorriyaz.in