Cambridge Past Paper Questions
Browse 23,045questions from 25 years of O-Level & A-Level exams. Click any question to practice.
In an experiment, 10 cm³ of an organic compound, J, in the gaseous state was sparked with an excess of oxygen. 20 cm³ of carbon dioxide and 5 cm³ o...
Three elements, X, Y and Z, have electronic configurations as shown. X 2,6 Y 2,8,1 Z 2,8,7 Which formulae represent compounds that conduct electric...
In this question, all gases can be assumed to behave ideally. A chemist heats a mixture of nitrogen and oxygen gases in a sealed container at a con...
An ethanol burner can be used to heat water. If appropriate measurements are taken, a value for the enthalpy of combustion of ethanol can be calcul...
The first ionisation energies of twenty successive elements in the Periodic Table are represented in the graph. The letters given are not the norma...
The diagram shows a compound used as a flame retardant. [Figure of brominated compound structure] Which statements about this structure are correct...
One of the active ingredients in tea-tree oil is terpinen-4-ol. In the diagram of the skeletal formula of terpinen-4-ol, three of the carbon atoms ...
Which syntheses will be successful? 1 CH₃CH₂CH₃ from CH₃CH=CH₂ + LiAlH₄ 2 CH₃CH(OH)CH₃ from CH₃COCH₃ + NaBH₄ 3 CH₃CH₂CH₂OH from CH₃CH₂CHO + NaBH₄
Which would contain 9.03 × 10²³ oxygen atoms?
In some fireworks there is a reaction between powdered aluminium and powdered barium nitrate. Heat is evolved, an unreactive gas is produced, and a...
Which organic compound has the highest boiling point?
At a temperature of 2500K and a pressure of 1.00 × 10⁻⁴Pa a sample of 0.321 g of sulfur vapour has a volume of 2.08 × 10⁻³ m³. What is the molecula...
Which reaction involves a decrease in the bond angle at a carbon atom?
In the high temperatures of car engines, nitrogen reacts with oxygen to give nitrogen monoxide. ½N₂(g) + ½O₂(g) → NO(g) ΔH° = +90 kJ mol⁻¹ This rea...
A reaction sequence is shown. 1 2 3 4 SO₂ SO₃ H₂SO₄ H₂S SO₂ In each stage of this sequence the sulfur is oxidised, reduced or neither oxidised nor ...
Hydrogen and carbon dioxide gases are mixed at 800 K. A reversible reaction takes place. H₂(g) + CO₂(g) ⇌ H₂O(g) + CO(g) At equilibrium, the partia...
A reaction involved in the Contact process is shown. 2SO₂(g) + O₂(g) ⇌ 2SO₃(g) ΔH° = –197 kJ mol⁻¹ The reaction is investigated at 200 kPa and 700 ...
The Boltzmann distribution for the hydrogenation of an alkene at a particular temperature in the absence of a catalyst is shown. [Figure 11.1] Whic...
The elements magnesium and sulfur each form doubly charged ions. How do the atomic radii and ionic radii of these elements compare?
Which graph correctly shows relative electronegativity plotted against relative atomic radius for the elements Na, Mg, Al and Si?
Trends are seen in the physical and chemical properties of the elements of Group 2 and their compounds. Which property shows a decrease from magnes...
Calcium oxide is added to water and the resulting mixture is filtered. This filtrate is X. When carbon dioxide is bubbled through filtrate X, a whi...
Element X reacts with cold, dilute, aqueous sodium hydroxide to form two different chlorine-containing products, Y and Z. What are the oxidation st...
A powder is known to be either a single sodium halide or a mixture of two sodium halides. A sample of the powder was dissolved in water. Aqueous si...
The ammonium ion is formed by the following reaction. NH₃ + H⁺ → NH₄⁺ Which statement about the species involved in this reaction is correct?
A chemist took 2.00 dm³ of nitrogen gas, measured under room conditions, and reacted it with a large volume of hydrogen gas to produce ammonia. Onl...
A carbonyl compound X will react with HCN in the presence of NaCN to make a compound with Mr 85. Compound X does not react with Fehling's reagent. ...
Geraniol and linalool are compounds found in some flower fragrances. [Figure 21.1] Which statement is correct?
Which equation represents the initiation step of the substitution reaction between methane and chlorine?
Aqueous sodium hydroxide reacts with 1-bromopropane to give propan-1-ol. What should be included in a diagram of the first step in the mechanism?
A sample of 2.76 g of ethanol was mixed with an excess of aqueous acidified potassium dichromate(VI). The reaction mixture was then boiled under re...
Compound X is a single, pure, optical isomer. X is heated with an excess of concentrated H₂SO₄. Only one organic product is formed. What could X be?
2-bromo-2-methylpropane undergoes nucleophilic substitution when heated under reflux with an aqueous solution of sodium hydroxide. Which row is cor...
H₂NNHC₆H₃(NO₂)₂ is the structural formula of 2,4-DNPH. Many, but not all, organic reactions need to be heated before reaction occurs. Which reactio...
A carboxylic acid, P, has no possible chain isomers. It reacts with an alcohol, Q, that has only one positional isomer. What could be the ester for...
Which compound is chiral and reacts with Na₂CO₃ to give CO₂?
Which compound, when hydrolysed, gives propanoic acid and propan-2-ol?
An isolated gaseous atom of element X has paired electrons in at least one of its 3d orbitals and has a filled 4s subshell. What could be the ident...
Which allotropes of carbon have a giant molecular structure? 1 buckminsterfullerene 2 diamond 3 graphite
Which statements about endothermic reactions are correct? 1 On the reaction pathway diagram the products of the reaction are lower than the reactan...
The rate of chemical reactions can be increased by the addition of a suitable catalyst. For which reactions can a heterogeneous catalyst be used? 1...
Which chlorides, when added to water, can produce a solution with a pH of less than 5? 1 SiCl₄ 2 AlCl₃ 3 MgCl₂
Acid rain continues to be a problem. Which statements about acid rain are correct? 1 Acid rain is formed when oxides of nitrogen or oxides of sulfu...
Which compounds contain a chiral centre? 1 2-hydroxybutanoic acid 2 3-hydroxybutanoic acid 3 4-hydroxybutanoic acid
The diagram shows the monomer used to make polyvinyl chloride, PVC. [Figure 38.1] Assuming that one particular molecule of the polymer forms from n...
An organic compound, X, has the following skeletal formula. [Figure 39.1] Which statements about X are correct? 1 X is a primary alcohol. 2 X will ...
2,2,4-trimethylpentanal is used in the manufacture of adhesives. Which reagents would 2,2,4-trimethylpentanal react with? 1 2,4-dinitrophenylhydraz...
Combustion data can be used to calculate the empirical formula, molecular formula and relative molecular mass of many organic compounds.
Structure and bonding can be used to explain many of the properties of substances.
The properties of elements and their compounds show similarities, differences and trends depending on the positions of the elements in the Periodic...