GCE Chemistry 2023
Past Questions

The atomic radius generally decreases across a period from left to right because

What is the mass of 0.25 mol of trioxonitrate(V) acid, HNO₃? [H = 1, N = 14, O = 16]

In the reaction $2H_2 + O_2 \rightarrow 2H_2O$, what mass of water is produced when 4 g of hydrogen reacts completely with excess oxygen? [H = 1, O = 16]

Which of the following statements correctly describes the process of hydrolysis of salts?

During the electrolysis of dilute sulphuric acid using platinum electrodes, which product is formed at the cathode?

Which of the following factors does NOT affect the rate of a chemical reaction?

Given that the activation energy of a reaction is 80 kJ mol⁻¹ and a catalyst lowers it to 50 kJ mol⁻¹, what is the reduction in activation energy?

At a certain temperature, the equilibrium constant $K_c$ for the reaction $H_2(g) + I_2(g) \rightleftharpoons 2HI(g)$ is 49. If the equilibrium concentrations of $H_2$ and $I_2$ are both $0.10\,mol\,d…

The process by which crude oil is separated into fractions of different boiling points is called

The oxide of a certain element dissolves in water to form an acidic solution. This element is most likely a

a) Distinguish between a reversible reaction and an irreversible reaction, giving one example of each. (4 marks) b) For the gaseous equilibrium: 2SO2(g) + O2(g) ⇌ 2SO3(g) ΔH = -196 kJ/mol i)…

The following reaction scheme involves an organic compound A (molecular formula C2H5OH): A + [O] → B + H2O B + [O] → C A + C → D + H2O (in the presence of concentrated H2SO4) A + Na → E + F (gas) (a) …