Soln:

At Anode
2OH → 2OH + 2e^-
2OH → H₂O + O
O + O → O₂

4OH_(aq)^- → 2H₂O_(I) + 4e^- + O_2(g)

4e^-migrate to the cathode

At cathode

Cu²⁺ + 2e^-→ Cu_(s)

Copper is deposited at the cathode
faradays of electricity supplied = Coulombs / 96000
= 8 × 80 × 60 / 96000
= 0.4

But

i) faraday = Atomic weight of Cu / valence of Cu²⁺ ion
= 64 / 2
= 32g

0.4 faraday of electricity will liberate = 0.4 × 32
= 12.8g
12.8g of copper was produced

ii)mass of O₂ = (Atomic mass of O₂ × faradays) / valiancy of O^{2 –} ion

= 16/2 × 0.4
= 3.2
Molar gas volume at r.t.p = 24dm³
32g of O2 gas occupy 24dm³ at r.t.p