Write a balanced equation for the oxidation of Co(II) to Co(III) by hydrogen peroxide. Why is this oxidation process assisted by the presence of ammonia?
a) Co(II) + H₂O₂ → Co(III) + H₂O
b) 2Co(II) + 2H₂O₂ + 4NH₃ → 2Co(III) + 4H₂O + N₂
c) 3Co(II) + 3H₂O₂ → 3Co(III) + 3H₂O
d) Co(II) + H₂O₂ + NH₃ → Co(III) + H₂O + N₂
