Cambridge Past Paper Questions
Browse 23,045questions from 25 years of O-Level & A-Level exams. Click any question to practice.
Which statements about bond angles are correct? 1 The bond angle in SO2 is smaller than the bond angle in CO2. 2 The bond angle in H2O is smaller t...
An energy profile diagram is shown. [Figure for energy profile diagram] What do the labels on the diagram represent? 1 W = ΔH of the forward reacti...
Which are assumptions of the kinetic theory of gases and hence of the ideal gas equation, PV = nRT? 1 Molecules move without interacting with one a...
Use of the Data Booklet is relevant to this question. Which properties would be expected for radium, ⁸⁸Ra, or its compounds? 1 Radium carbonate wou...
When a firework is lit, a fuel and an oxidising agent react together. In one such firework, magnesium is the fuel and barium nitrate is the oxidisi...
Compound X has molecular formula C4H10O. Separate samples of X are tested with three different reagents. Which results could not be obtained?
Y is an organic compound. Y gives a precipitate with aqueous silver nitrate. All of this precipitate dissolves when concentrated aqueous ammonia is...
Which compounds will produce ethanoic acid when boiled under reflux with dilute alkali followed by acidification? 1 CH3CH2Cl 2 CH3CO2CH3 3 CH3CN
Which pairs of homologous series have the same C:H ratio in their general formulae? 1 aldehydes and ketones 2 carboxylic acids and esters 3 alkenes...
In which reaction does an element undergo the largest change in oxidation state?
Use of the Data Booklet is relevant to this question. The 68Ge isotope is medically useful because it undergoes a natural radioactive process to gi...
Sodium borohydride, NaBH4, and boron trifluoride, BF3, are compounds of boron. What are the shapes around boron in the borohydride ion and in boron...
Use of the Data Booklet is relevant to this question. A reaction which causes the presence of oxides of nitrogen in car exhausts is the formation o...
In the table below, • '+' means that this type of standard enthalpy change can only have positive values, • '-' means that this type of standard en...
Use of the Data Booklet is relevant to this question. The volume of a sample of ammonia is measured at a temperature of 60°C and a pressure of 103 ...
Aluminium is extracted by the electrolysis of a molten mixture containing aluminium oxide. By a similar method, magnesium is extracted by the elect...
Some car paints contain small flakes of silica, SiO2. In the structure of solid SiO2 • each silicon atom is bonded to x oxygen atoms, • each oxygen...
John Dalton's atomic theory, published in 1808, contained four predictions about atoms. Which of his predictions is still considered to be correct?
A student calculated the standard enthalpy change of formation of ethane, C2H6, using a method based on standard enthalpy changes of combustion. He...
Which process could be used to calculate the bond energy for the covalent bond X-Y by dividing its ΔH by n?
In which pair do the molecules have the same shape as each other?
Why is the ionic radius of a chloride ion larger than the ionic radius of a sodium ion?
What are the trends in the stated properties as Group II is descended from magnesium to barium?
Use of the Data Booklet is relevant to this question. The nitrates of beryllium, calcium, magnesium, and strontium all decompose in the same way wh...
In a car engine, non-metallic element X forms a pollutant oxide Y. Y can be further oxidised to Z. Two students made the following statements. Stud...
Use of the Data Booklet is relevant to this question. 1.15 g of a metallic element reacts with 300 cm³ of oxygen at 298 K and 1 atm pressure, to fo...
Elements X and Y are both in period three. When the chloride of X is added to water, it reacts and a solution of pH 2 is produced. When the chlorid...
Which diagram shows the variation of the metallic radius r of the Group I elements, Li, Na, K and Rb, with increasing proton (atomic) number?
Carvone is found in spearmint. [Figure 20.1] How many σ and π bonds are present in this molecule?
An alkene has the formula CH3CH=CRCH2CH3 and does not possess cis-trans isomers. What is R?
Menthol is an important compound extracted from the peppermint plant. [Figure 22.1] How many chiral centres are there in one molecule of menthol?
The cracking of a single hydrocarbon molecule, CnH2n+2, produces two hydrocarbon molecules only. Each hydrocarbon product contains the same number ...
But-2-ene-1,4-diol is converted in two steps through an intermediate X into ketobutanedioic acid. [Figure 24.1] What could be the reagent for step ...
One of the reactions taking place in a catalytic converter in a car exhaust system is between nitrogen oxide and octane (unburned petrol). The prod...
High-energy radiation in the stratosphere produces free-radicals from chlorofluoroalkanes, commonly known as CFCs. Which free-radical is most likel...
Which reagent reacts with ethanol and also reacts with ethanoic acid?
In 1903 Arthur Lapworth became the first chemist to investigate a reaction mechanism. The reaction he investigated was that of hydrogen cyanide wit...
Compound X, C6H12O, is oxidised by acidified sodium dichromate(VI) to compound Y. Compound Y reacts with ethanol in the presence of a little concen...
How may nitrogen exist in compounds? 1 bonded by a triple covalent bond 2 as part of a cation 3 having lost 3 electrons to form an anion
Use of the Data Booklet is relevant to this question. The isotope 99Tc is radioactive and has been found in lobsters and seaweed adjacent to nuclea...
Which of these substances have a giant structure? 1 silicon(IV) oxide 2 baked clay found in crockery 3 phosphorus(V) oxide
The element astatine, At, is below iodine in Group VII of the Periodic Table. Which statements concerning At will be correct? 1 It is a dark-colour...
Which equations represent stages in the Contact process for manufacturing sulfuric acid? 1 SO2 + ½ O2 → SO3 2 SO2 + H2O → H2SO3 3 H2SO3 + ½ O2 → H2SO4
When added to water, which oxides will not cause a change in pH? 1 Al2O3 2 SiO2 3 P4O10
Which reagents and conditions will convert propane into 1-chloropropane? 1 Cl2 and sunlight 2 conc. HCl, reflux 3 PCl5
Chloroethane can be formed from bromoethane in two steps. C2H5Br --(step X)--> C2H5OH --(step Y)--> C2H5Cl Which statements about these steps are c...
Which reagents react with butanone, C2H5COCH3? 1 Tollens' reagent 2 sodium borohydride 3 2,4-dinitrophenylhydrazine reagent
Oleic acid is found in olive oil. It has the following formula. [Figure 40.1] Which reagents will give a positive result with oleic acid? 1 aqueous...
At the age of 17, in a woodshed in Ohio, Charles Martin Hall discovered the commercial process for the production of aluminium metal by the electro...
In which reaction does a single nitrogen atom have the greatest change in oxidation number?