Split the following redox reactions into the oxidation and reduction half reactions:
(a) 2K(s) + Cl2(g) ⟶ 2KCl(s)
(b) 2Al(s) + 3Cu2+(aq) ⟶ 2Al3+(aq) + 3Cu(s)
(a) K(s) ⟶ K+(g) + e− [×2 … Oxidation
Cl2(g) + 2e− ⟶ 2Cl−(g) … Reduction
K+(g) + Cl−(g) ⟶ KCl(s) [×2
2K(s) + Cl2(g) ⟶ 2KCl(s) … Overall redox reaction
(b) Al(s) ⟶ Al3+(aq) + 3e− [×2 … Oxidation
Cu2+(aq) + 2e− ⟶ Cu(s) [×3 … Reduction
2Al(s) + 3Cu2+(aq) ⟶ 2Al3+(g) + 3Cu(s)… Overall redox reaction