An aqueous solution of nickel (II) sulphate was electrolyzed

Electrolysis (10)

An aqueous solution of nickel (II) sulphate was electrolyzed using nickel electrodes. Observe the diagram and answer the questions that follow:

(i) What do you observe at the cathode and anode respectively?

(ii) Name the cation that remains as a spectator ion in the solution.

(iii) Which equation for the reaction at the anode is correct?

  1. Ni → Ni2+ + 2e-
  2. Ni + 2e- → Ni2+
  3. Ni2+ → Ni + 2e-
  4. Ni2+ + 2e- → Ni

Answer

(i) Cathode - silvery metal deposited or coated or sticks / nickel or metal is deposited or coated or sticks / silvery deposit/increases in size or mass

Anode - Size decreases / reduction in mass / Anode dissolves / Anode Diminishes / Anode loses weight

(ii) Hydrogen ion or H+ or hydrogen

(iii) 1 or Ni → Ni2+ + 2e-

  • Exam Year: 2020