Cambridge Past Paper Questions
Browse 23,045questions from 25 years of O-Level & A-Level exams. Click any question to practice.
What is the major product formed when compound Q is warmed with excess HBr? [Figure]
Four students, W, X, Y and Z, made the following statements about alkanes and alkenes. W 'Bromine reacts with alkanes by electrophilic substitution...
Butanedioic acid may be synthesised in two steps from 1,2-dibromoethane. BrCH₂CH₂Br --step 1--> X --step 2--> HO₂CCH₂CH₂CO₂H Which reagents could b...
Which reaction would not give propene?
Terpinen-4-ol is one of the active ingredients in tea tree oil. [Figure] What is the molecular formula of terpinen-4-ol?
Use of the Data Booklet is relevant to this question. 2.40 g of propan-2-ol were mixed with excess acidified potassium dichromate(VI). The reaction...
The diagram shows the structure of compound X. [Figure] What is the product of the reaction between compound X and an excess of NaBH₄?
Lactic acid occurs naturally, for example in sour milk. [Figure] What is a property of lactic acid?
Citric acid is found in lemon juice. HO₂CCH₂C(OH)(CO₂H)CH₂CO₂H citric acid What is the volume of 0.4 mol dm⁻³ sodium hydroxide solution required to...
The drug Sirolimus is used to treat patients after kidney transplants. [Figure] On reaction with hot aqueous sodium hydroxide, Sirolimus produces a...
Use of the Data Booklet is relevant to this question. Which statements about the phosphide ion, ³¹P³⁻, and the chloride ion, ³⁵Cl⁻, are correct? 1 ...
Why does aluminium chloride, Al₂Cl₆, sublime at the relatively low temperature of 180°C? 1 The intermolecular forces between the Al₂Cl₆ molecules a...
Which statements are correct for all exothermic reactions? 1 ∆H for the reaction is negative. 2 On a reaction pathway diagram the products are show...
Which of these reactions are redox reactions? 1 6NO(g) + 4NH₃(g) → 5N₂(g) + 6H₂O(g) 2 2SO₂(g) + O₂(g) → 2SO₃(g) 3 SO₃(g) + H₂O(g) → H₂SO₄(g)
When added to water, which oxides will cause a change in the pH of the water? 1 SiO₂ 2 CaO 3 SO₂
Halogenated hydrocarbons have many uses. What have halogenated hydrocarbons been used for? 1 solvents 2 refrigerants 3 monomers in polymer manufacture
In which structures do the four carbon atoms labelled C lie in the same plane? 1 [Figure] 2 [Figure] 3 [Figure]
Which statements about 2-methylbutan-1-ol are correct? 1 It can give HCl(g) on reaction with PCl₅. 2 It can be oxidised to give an aldehyde. 3 It e...
Propanone and hydrogen cyanide react together by this mechanism. [Figure] Which statements about this mechanism are correct? 1 CN⁻ is an electrophi...
Monopotassium citrate is used as an emulsifying agent in powdered milk and in powdered soups. It may be represented by the formula shown. CH₂CO₂H H...
The diagram shows the Boltzmann distribution of energies in 1 mole of a gas. The gas can take part in a reaction with an activation energy, Ea. [Fi...
Four electronic configurations are shown below. Three of these configurations belong to atoms of the elements chlorine, sodium and vanadium. Which ...
Elements X and Y are in the same group of the Periodic Table. The table shows the first six ionisation energies of X and Y in kJ mol¯¹. 1st: X 800,...
In China, the concentration of blood glucose, C₆H₁₂O₆, is measured in mmol / l. In Pakistan, the concentration of blood glucose is measured in mg /...
Each of the four species in this question are isolated and gaseous. Which species is not planar?
Argon is a gas used to fill electric light bulbs. Under which conditions of pressure and temperature will argon behave most like an ideal gas? pres...
0.10 g of the volatile liquid X formed 0.025 dm³ of vapour at 100 °C and atmospheric pressure. 1 mol of vapour occupies 22.4 dm³ at 0 °C and atmosp...
The equation for the complete combustion of propan-1-ol is shown. CH₃CH₂CH₂OH(l) + 4½ O₂(g) → 3CO₂(g) + 4H₂O(l) Standard enthalpy changes of format...
In the treatment of domestic water supplies, chlorine is added to the water to form HClO. Cl₂(aq) + H₂O(l) → H⁺(aq) + Cl⁻(aq) + HClO(aq) The HClO r...
When solid ammonium chloride dissociates at a certain temperature in a 0.500 dm³ container, ammonia and hydrogen chloride are formed. NH₄Cl(s) ⇌ NH...
Which stage in the free radical substitution of ethane by chlorine has the lowest activation energy?
Sodium and sulfur react together to form sodium sulfide, Na₂S. How do the atomic radius and ionic radius of sodium compare with those of sulfur? at...
Solid aluminium chloride sublimes at 178 °C. Which structure best represents the species in the vapour at this temperature?
A 0.005 mol sample of anhydrous calcium carbonate was completely thermally decomposed to give 100 cm³ of gas measured at a certain temperature and ...
Ammonia gas, NH₃, and hydrogen sulfide gas, H₂S, react together to form the salt ammonium sulfide, (NH₄)₂S. Ammonium sulfide dissolves in water to ...
A solid, T, was placed in an excess of the liquid U. A colourless gas was given off and a white precipitate was seen. The precipitate was not T. Wh...
Nitrogen(II) oxide, NO, nitrogen(IV) oxide, NO₂, carbon monoxide, CO, and unburnt hydrocarbons are present in the exhaust gases of internal combust...
An excess of chlorine gas, Cl₂, is passed through 60 cm³ of cold aqueous 0.1 mol dm⁻³ sodium hydroxide. In a separate experiment an excess of chlor...
Fluorine and iodine are Group 17 elements. Their melting points are different due to differing strengths of van der Waals' forces between molecules...
Chlorofluorocarbons damage the ozone layer by undergoing reactions with a free radical mechanism. The first stage of this is initiation. Which equa...
Synthetic resins can be made by polymerisation of a variety of monomers including prop-2-en-1-ol, CH₂=CHCH₂OH. Which structure represents the repea...
Oct-1-ene, CH₃(CH₂)₅CH=CH₂, can be thermally cracked. Which combination of compounds W, X, Y and Z can be obtained by thermally cracking oct-1-ene?...
A cycloalkene with the molecular formula C₇H₁₂ was oxidised by hot concentrated acidified MnO₄. The only organic product was 2-methylhexane-1,6-dio...
1-chloro-1-methylcyclohexane is hydrolysed by heating with NaOH(aq). The reaction pathway is shown. [Diagram showing reaction path and energy profi...
Malic acid is found in apples. [Figure of malic acid structure] Which reagent will react with only one of the –OH groups in the malic acid molecule?
Which organic compound would not give either a yellow precipitate when treated with alkaline aqueous iodine or an orange precipitate when treated w...
In which reaction is the organic compound oxidised?
How many of the following compounds produce a carboxylic acid on heating under reflux with an excess of hot acidified K₂Cr₂O₇? CH₃CH₂CHO, CH₃COCH₃,...
How many isomeric esters, including structural isomers and stereoisomers, can be made with the molecular formula C₅H₁₀O₂, if methanoic acid is one ...
Compound X, C₄H₈O₂, has an unbranched carbon chain. An aqueous solution of X has an approximate pH of 3. Compound Y, C₃H₈O, is a secondary alcohol....