Question

An electrolytic cell is set up using two platinum electrodes and an aqueous solution of copper (II) sulphate,
(a)draw a labelled diagram of the electrolytic cell,
(b)Name the ions present in the cell,
(c)Name the ions migrating towards the anode,
(d)Name the ions migrating towards the cathode,
(e)Name the ions which will not be discharged at electrodes during electrolysis,
(f)Write the reaction at the cathode,
(g)Write the reaction at the anode,
(h)Name the spectator ion in the solution.

Answer 1

(a) Labelled diagram of electrolytic cell is:

(b) The ions present in the cell are Cu²⁺, H⁺, SO₄^2-, OH^-.
(c) SO₄^2- and OH^- ions both migrate towards anode.
(d) Both Cu²⁺ and H⁺ ions migrate towards cathode.
(e) SO₄^2- and H⁺ will not discharge at electrodes.
(f) Reaction at cathode:
Cu⁺² +2e^- ⟶ Cu
(g) Reaction at anode:
OH^- - e^- ⟶ OH
2OH + 2OH ⟶ 2H₂O + O₂
(h) Sulphate ions are the spectator ions because they do not change in the reaction.