Cambridge Past Paper Questions
Browse 23,045questions from 25 years of O-Level & A-Level exams. Click any question to practice.
Asparagine and valine are two naturally occurring amino acids. [Figure showing structures of asparagine and valine]
Calcitriol is a steroid hormone found in human blood. [Figure showing structure of calcitriol]
Benzene reacts with D in the presence of a suitable catalyst to give cumene and non-organic product E. This is an electrophilic substitution reacti...
The three substances shown all have some acidic properties. [Figure showing structures of propanoic acid, propan-1-ol, phenol]
Abscisic acid, C15H20O4, is a plant hormone. [Figure showing structure of abscisic acid]
Noradrenaline is a hormone found in humans. [Figure showing structure of noradrenaline]
The Faraday constant is the charge in coulombs, C, carried by 1 mole of electrons.
At temperatures above 5°C, the benzenediazonium ion, C₆H₅N₂⁺, reacts with water as shown. C₆H₅N₂⁺(aq) + H₂O(l) → C₆H₅OH(aq) + N₂(g) + H⁺(aq) A st...
When concentrated iron(III) chloride is added to water at just below boiling point, a reaction occurs and produces Fe2O3, seen as a red colour in t...
Water boils when the pressure of its vapour above the liquid surface is equal to the atmospheric pressure. When substances are dissolved in water, ...
At temperatures above 5°C, the benzenediazonium ion, C₆H₅N₂⁺, reacts with water as shown. C₆H₅N₂⁺(aq) + H₂O(l) → C₆H₅OH(aq) + N₂(g) + H⁺(aq) A stud...
The Boltzmann distribution of molecular energies in a sample of aqueous hydrogen peroxide at room temperature is shown. [Figure 1.1] Which diagram ...
Oxygen has three stable isotopes, 16O, 17O and 18O. All three isotopes are present in a sample of oxygen gas, O2, which was analysed using a mass s...
The first eight successive ionisation energies for two elements of Period 3 of the Periodic Table are shown in the graphs. [Figure 3.1] What is the...
A σ bond is made between two carbon atoms in a molecule of ethene. Which diagram shows the orbital overlap that occurs to form this bond?
The table shows some properties of four substances. Which substance could be potassium iodide? melting point of solid/°C electrical conductivity wh...
X, Y and Z are all gases that behave ideally and react according to the equation shown. X(g) + 2Y(g) → 2Z(g) When 3.0 mol of X and 3.0 mol of Y are...
Which pair of substances are both simple molecular?
A reaction pathway diagram is shown. [Figure 8.1] Which row is correct? enthalpy change of the forward reaction activation energy of the reverse ...
X is either chlorine or an oxide of chlorine. X reacts with water, under suitable conditions, to form the two acids HCl and HClO3 in the mole ratio...
Ethyl ethanoate undergoes the following reaction. CH3CO2C2H5 + H2O ⇌ C2H5OH + CH3CO2H Kс = 0.27 Equal amounts of ethanoic acid and ethanol were mix...
Which row is an example of heterogeneous catalysis? reaction catalyst A esterification sulfuric acid B the Contact process divanadium pentoxide C d...
Element Q readily oxidises in air. The oxide produced reacts with water to form a solution of very low pH. Where could element Q be found in the Pe...
The eight elements sodium to argon are in the same period of the Periodic Table. The equation corresponding to the first ionisation energy is shown...
Elements D and E are both in Period 3. Element D has the smallest atomic radius in Period 3. There are only two elements in Period 3 which have a l...
How many of the solutions shown, when added to separate portions of magnesium sulfate solution, produce a white precipitate? HCl(aq) NH3(aq) (NH4)2...
A white solid, Z, is soluble in water. A sample of Z is heated with a Bunsen burner until there is no further change. When the residue is shaken wi...
Ammonium sulfate, (NH4)2SO4, and ammonium nitrate, NH4NO3, are used as fertilisers. These salts have different percentages by mass of nitrogen. The...
Which reaction gives a product that is an atmospheric pollutant causing acid rain?
3-methylbut-1-ene can undergo different types of reaction. [Figure 20.1] Which row correctly identifies the reaction types? reaction 1 reaction 2 A...
Compound X does not show cis-trans isomerism. What could be the identity of compound X?
The diagram shows the repeat unit of an addition polymer. [Figure 22.1] What is the correct name for the monomer that would form this polymer?
A molecule of geraniol is shown. [Figure 23.1] What is formed when geraniol is reacted with an excess of cold, dilute, acidified manganate(VII) ions?
Alcohol W cannot be made by reducing a carboxylic acid with LiAlH4. Alcohol W gives only one product when dehydrated with concentrated sulfuric aci...
Which product can be made from bromoethane by an elimination reaction?
Propene, bromine and hydrogen bromide are mixed in the dark. A number of products are formed, some in very small quantities. Which substance will n...
Which reagent could be used to distinguish between ethanal and propanal?
The diagram shows that a carboxylic acid P may be formed from X, Y or Z. [Figure 28.1] Which row is correct? alcohol X is the change in Mᵣ is great...
One molecule of compound R is shown. [Figure 29.1] What is the name of compound R and how does its boiling point compare with that of butanoic acid?
The diagram shows the infra-red spectrum of Q. [Figure 30.1] What could be Q?
When O2 reacts with H2S the products are SO2 and H2O. Mixture Y contains an equal number of the two molecules shown, and no other molecules. [Figur...
Which statements about an atom of ⁹⁹Tc are correct?
In which reactions are nitrogen atoms reduced?
The manufacture of ammonia from nitrogen and hydrogen is an important industrial process. Which of the following would leave the equilibrium consta...
Which reactions involving calcium and its compounds produce two gaseous products?
A small quantity of hot, concentrated sulfuric acid is added separately to solid samples of potassium halides, KX. Which potassium halides react an...
The diagram shows a compound used as a flame retardant. [Figure 37.1] Which statements about this structure are correct?
Halogenoalkanes can be hydrolysed using aqueous sodium hydroxide. Which compounds tend to be hydrolysed by an Sɴ1 mechanism?
In an organic synthesis, a 62% yield of product is achieved. Which conversions are consistent with this information?
An oxidising agent that can oxidise ethanal to ethanoic acid or ethanoate ions will also oxidise methanoic acid, HCO2H, to carbon dioxide and water...