Cambridge Past Paper Questions
Browse 23,045questions from 25 years of O-Level & A-Level exams. Click any question to practice.
The airbags in cars contain sodium azide, NaN3, and an excess of potassium nitrate, KNO3. In a car accident, the reactions shown occur, producing n...
Ethane burns in oxygen to produce carbon dioxide and water vapour. Which bond angles are present in the molecules of ethane and its combustion prod...
A sample of an ideal gas is contained at a constant temperature of 300 K in a gas syringe. The pressure is increased and a graph of pV/RT against p...
In calculating the enthalpy change, ∆H, of an experiment involving solutions, the mass of the solution, m, specific heat capacity of the solution, ...
The following data are needed for this question. ∆Hᶠ (P4O10(s)) = −3012 kJ mol⁻¹ ∆Hᶠ (H2O(l)) = −286 kJ mol⁻¹ ∆Hᶠ (H3PO4(s)) = −1279 kJ mol⁻¹ What ...
Which statement is always correct for an oxidation reaction?
Nitrogen dioxide, NO2, is a brown gas. Dinitrogen tetroxide, N2O4, is a colourless gas. An equilibrium is established between NO2 and N2O4 in a clo...
A large excess of marble chips was reacted with 25 cm³ of 1.0 mol dm⁻³ hydrochloric acid at 40 °C. How will the result be different when the reacti...
Which change alters the activation energy of a given reaction?
Element Z has a giant structure. The chloride of Z reacts with water to give a solution with a pH less than 5. Which row shows two elements which c...
Radium is an element below barium in Group 2 of the Periodic Table. Which equation shows what happens when solid radium nitrate, Ra(NO3)2, is heate...
Exactly 3.705 kg of substance Y are needed to neutralise 100 moles of HCl(aq). What could be substance Y?
In an experiment, 0.125 mol of chlorine gas, Cl2, is reacted with an excess of cold, aqueous sodium hydroxide. One of the products is a compound of...
Sodium bromide reacts with concentrated sulfuric acid. Which observation will be made?
The reaction of nitrogen and oxygen to produce oxides of nitrogen happens at high temperatures in car engines or lightning strikes during thunderst...
X is a mixture of two compounds of Group 2 elements. X undergoes thermal decomposition to produce a white solid and only two gaseous products. One ...
Which compound does not exhibit stereoisomerism?
The diagram shows the skeletal formula of citric acid. [Figure 21.1 - skeletal formula of citric acid] What is the molecular formula of citric acid?
Which compound would produce two different carboxylic acids when treated with hot, concentrated, acidified manganate(VII) ions?
Which types of bond are broken and formed in the addition polymerisation of alkenes?
2,3-dimethylpent-2-ene, (CH3)2C=C(CH3)CH2CH3, is treated with cold, dilute KMnO4. The product of this reaction is treated with an excess of concent...
Equal volumes of aqueous silver nitrate were added to separate small volumes of bromoethane and iodoethane in two test-tubes. The test-tubes were s...
Many, but not all, organic reactions need to be heated before a reaction occurs. Which reaction occurs quickly at room temperature (20 °C)?
When compound X is warmed with dilute, acidified potassium dichromate(VI) there is no colour change. X does not give an orange precipitate with 2,4...
Compound G • has a chiral centre, • gives a positive result with alkaline aqueous iodine, • does not give a silver mirror with Tollens' reagent. Wh...
An ester with an odour of banana has the following formula. CH3CO2CH2CHCH2CH3 | CH3 Which pair of reactants, under suitable conditions, will produc...
In 2011 an international group of scientists agreed to add two new elements to the Periodic Table. Both elements had been made artificially and are...
The chlorine oxide free radical, ClO•, is produced by the reaction between chlorine atoms and ozone. Cl + O3 → ClO• + O2 Which features are present...
Hydrogen sulfide can be oxidised to form sulfur dioxide. 2H2S + 3O2 → 2SO2 + 2H2O Which statements are correct? 1 The oxidation number of sulfur in...
Methanoic acid, HCO2H, and hydrocyanic acid, HCN, can both behave as acids. A solution of methanoic acid has a lower pH than a solution of hydrocya...
Which statements correctly describe a trend on going down Group 2? 1 Reactivity of the elements increases. 2 First ionisation energy of the element...
Modern cars are fitted with catalytic converters to reduce atmospheric pollution caused by unwanted reactions during the combustion of the fuel. Wh...
Which statements are correct for an SN2 mechanism? 1 One bond is being broken at the same time as another bond is being formed. 2 The formation of ...
Bromoethane is heated under reflux with concentrated aqueous NaOH. Which statements are correct? 1 The major product is a primary alcohol. 2 The ma...
Compound M is an important ingredient in perfume. [Figure 39.1 - skeletal formula of compound M] M reacts with HCN. Which statements about this rea...
Carboxylic acids can be converted into their salts by a number of reactions at room temperature. Which reactions would produce sodium butanoate and...
Ammonia, NH3, is manufactured from nitrogen and hydrogen by the Haber process. N2(g) + 3H2(g) ⇋ 2NH3(g) ΔH = –92 kJ mol-1
The elements in the third period, and their compounds, show trends in their physical and chemical properties.
Some reactions based on 1-bromobutane, CH3(CH2)3Br, are shown. [Figure X.X] (Diagram shows a reaction scheme with CH3(CH2)3OH, CH3(CH2)3Br, CH3CH2C...
The elements sodium to sulfur react with chlorine. The melting points of some of the chlorides formed are shown. chloride | NaCl | MgCl2 | AlCl3 | ...
At 450 K phosphorus(V) chloride, PCl5(g), decomposes to form phosphorus(III) chloride, PCl3(g), and chlorine, Cl2(g). A dynamic equilibrium is esta...
The elements in Group 2 show trends in their properties that are typical of metals. The elements in Group 17 show trends in their properties that a...
Some reactions are shown, based on methylpropan-2-ol, (CH3)3COH. [Figure showing reaction scheme: (CH3)3CBr (reaction 1) → (CH3)3COH (reaction 2) →...
Ammonia, NH3, is manufactured from nitrogen and hydrogen by the Haber process. N2(g) + 3H2(g) ⇌ 2NH3(g) ΔH = –92 kJ mol–1
Some reactions based on 1-bromobutane, CH3(CH2)3Br, are shown. [Figure 3.1: Reaction scheme diagram]
In this experiment you will determine the oxidation number of iodine in one of its compounds by titration. FA 1 is a 0.0197 mol dm-³ solution of th...
Zinc carbonate occurs in a basic form, which means that zinc hydroxide is also present. The chemical formula of basic zinc carbonate can be written...
Qualitative Analysis At each stage of any test you are to record details of the following: • colour changes seen; • the formation of any precipitat...
In this experiment you will determine the value of x in the formula for hydrated copper(II) sulfate, CuSO4.xH2O. You will first react a solution of...
In this experiment you will determine the value of y in the formula for hydrated barium chloride, BaCl2.yH2O. You will do this by measuring the mas...