Balanced chemical equations for each of the reactions, including phases and using a forward reaction arrow in both equations:

a) 2H₂(g) + O₂(g) → 2H₂O(l)
b) CH₄(g) + 2O₂(g) → CO₂(g) + 2H₂O(g)
c) 2Mg(s) + O₂(g) → 2MgO(s)
d) 2Al(s) + 3CuCl₂(aq) → 3Cu(s) + 2AlCl₃(aq)