Test learner’s knowledge of equilibria with this question and answer sheet. 

The topics covered in this Starter for ten activity are: the equilibrium constant, Kc, calculations with Kc, Le Châtelier and Kc, the equilibrium constant, Kpthe solubility product, Ksp. 

Example question

Match each of the reactions to the correct description;

 Wood burning  Heating hydratedCuSO4.5H2O Making an ester;CH3COOH(aq) + CH3OH(aq)⇌CH3COOCH3(aq) + H2O(aq)

A reversible reaction at equilibrium


A reversible reaction


An irreversible reaction

Explain your choice. 

We can define a constant, Kc for a reaction at equilibrium. Provided the temperature is constant, the value of Kc is constant.

For each of the equilibria below, write an expression for the rate constant, Kc and derive the units of the constant.

(a) Electrophilic addition of HCN to propanone;

CH3COCH3(aq) + HCN(aq) ⇌ CH3C(OH)(CN)CH3(aq)

 Kc =                                   Units =

(b) Esterification;

CH3CH2COOH(aq) + CH3OH(aq) ⇌ CH3CH2COOCH3(aq) + H2O(aq)

Kc =                                   Units =

(c) The Haber Process;

N2(g) + 3 H2(g) ⇌ 2 NH3(g)

Kc =                                   Units =


A full version of this question and answer sheet is available from the ‘downloads’ section below. An editable version is also available.