Write equations for the reactions taking place at the two electrodes (mentioning clearly the name of the electrode) during the electrolysis of:

(i) Electrode — Cathode : Copper, Anode : Copper

Dissociation of aq. CuSO₄ :

CuSO₄ ⇌ Cu²⁺ + SO₄^2-

H₂O ⇌ H¹⁺ + OH^1-

H₂SO₄ ⇌ 2H¹⁺ + SO₄^2-

Reaction at cathode [pure thin sheet of Cu]:
Cu²⁺ + 2e^- ⟶ Cu [Cu deposited on thin sheet]

Reaction at anode [impure block of active Cu]:
Cu - 2e^- ⟶ Cu²⁺ [product nil - Cu²⁺ ions]

(ii) Electrode — Cathode : Iron or Graphite, Anode : Graphite

Dissociation of molten PbBr₂ : PbBr₂ ⇌ Pb²⁺ (cathode) + 2Br^1- (anode)

Reaction at cathode:
Pb²⁺ + 2e^- ⟶ Pb [product lead metal]

Reaction at anode:
Br^1- - 1e^-⟶ Br
Br + Br ⟶ Br₂