Cambridge Past Paper Questions
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When an organic acid, RCOOH, is neutralised by an alkali an exothermic reaction takes place. You will determine the enthalpy change of neutralisati...
Answer all the questions in the spaces provided. (a) An aqueous solution of cobalt(II) contains the [Co(H2O)6]2+ complex ion.
The overall reaction for photosynthesis is shown. 6CO2 + 6H2O → C6H12O6 + 6O2 Water is oxidised in this process according to the following half-equ...
The molecular formulae of three nitrogen-containing compounds are given. S C6H5CONH2 T C6H5NH2 U C6H5CH2NH2
(a) Benzene reacts with bromine in the presence of an aluminium bromide catalyst, AlBr3, to form bromobenzene. This is a substitution reaction. No ...
(a) Silver carbonate, Ag2CO3, is sparingly soluble in water. The numerical value of the solubility product, Ksp, for silver carbonate is 6.3 × 10–1...
(a) Manganese(IV) oxide, MnO2, catalyses the decomposition of hydrogen peroxide, H2O2, as shown. MnO2 2H2O2(aq) → 2H2O(l) + O2(g) The mechanism inv...
EDTA⁴⁻, is a polydentate ligand.
The class of polymers called polycarbonates are made by the reaction of carbonyl dichloride, COCl₂, with a diol. a diol n HOROH + n COCl₂ → a poly...
An aqueous solution of cobalt(II) contains the [Co(H2O)6]2+ complex ion.
Benzene reacts with bromine in the presence of an aluminium bromide catalyst, AlBr3, to form bromobenzene. This is a substitution reaction. No addi...
Silver carbonate, Ag2CO3, is sparingly soluble in water. The numerical value of the solubility product, Ksp, for silver carbonate is 6.3 × 10–12 at...
The electronic configuration of transition element Q is [Ar] 3d² 4s².
Trichloromethane and propanone are both organic liquids. The molecules within each liquid are attracted to each other by relatively weak permanent ...
Nitrogen dioxide can be prepared by strongly heating anhydrous lead nitrate, Pb(NO₃)₂(s). The thermal decomposition occurs according to the equatio...
A student plans to carry out an experiment to find the relative molecular mass, Mr, of a soluble acidic gas, X, by finding the mass of a measured v...
Each student in a class of nine students performs an experiment to find the formula of a chloride of iron. Each student prepares the chloride of ir...
Which statement about the Avogadro constant is correct?
Which equation represents the first ionisation energy of iodine?
The structures represent three compounds, each with four carbon atoms per molecule. [Diagram X: CH₃CH₂CH₂COOH] [Diagram Y: CH₃COOCH₂CH₃] [Diagram Z...
The structural formula of alliin is shown. [Diagram of alliin with bond angles x, y, z marked] What are the approximate bond angles x, y and z in a...
Flask Q contains 5 dm³ of helium at 12 kPa pressure. Flask R contains 10 dm³ of neon at 6 kPa pressure. If the flasks are connected at constant tem...
Sodium chloride, water and air represent three states of matter – solid, liquid and gas. Which row is correct?
The reaction pathway diagram for the catalysed reaction and the uncatalysed reaction between N₂ and H₂ is shown. N₂(g) + 3H₂(g) ⇌ 2NH₃(g) [Reaction...
Nitrogen and oxygen can react together to form nitrogen monoxide, NO. N₂ + O₂ ⇌ 2NO ΔH = +180 kJ mol⁻¹ What is the bond energy of the bond between ...
The equation for a redox reaction is shown. SnCl₂(aq) + 2HgCl₂(aq) → SnCl₄(aq) + Hg₂Cl₂(s) Which species is being oxidised in this reaction?
3.60 moles of hydrogen gas and 2.00 moles of iodine vapour are placed in a reaction vessel which is then sealed and maintained at a constant temper...
Two chemicals, X and Y, react together in solution to give product Z. The rate of formation of product Z at the start of the reaction was measured ...
A sample of SiCl₄ is added to cold water. Which statement describes the mixture formed at the end of the reaction?
L and M are elements in Period 3 of the Periodic Table. • The oxide of L is a solid at room temperature. This oxide has a giant structure. • The ch...
A farmer requires a solid compound to raise the pH of the soil in a field from 5.5 to above 6.0. Which compound could the farmer use?
Which row gives mixtures that both result in the oxidation of a halide ion?
Chlorine gas is widely used to treat contaminated water. When chlorine is added to water, which chemical species present is responsible for killing...
What is an environmental consequence of the uncontrolled use of nitrate fertilisers?
Compound P is treated with an excess of hydrogen gas in the presence of a nickel catalyst. The product Q is fully saturated. [Diagram of compound P...
Hexadeca-10,12-dien-1-ol is produced by silk moths from hexadecanoic acid in a three-step enzymic process. [Reaction scheme from hexadecanoic acid ...
Compound X can be converted into compound Y in a single step. [Reaction scheme X to Y with structures] What could be the identity of X?
Methane and bromine react by free radical substitution. P and Q are involved in the reaction mechanism. • are both involved in propagation steps as...
A few drops of 2-bromopropane were placed in a test-tube. An equal volume of aqueous silver nitrate was added. A precipitate was formed. The experi...