Помогите составить 3 предложения со словом than. 

1. Hg → Hg + O2;                                                                    31. KOH + AlCl3 → Al(OH)3 + KCl;

2. Zn + H2SO4  → ZnSO4 + H2;                                               32. CH4 + O2→ CO2 + H2O;

3. Na2S + Pb(NO3)2→ PbS + NaNO3                                      33. FeO + HCl → FeCl2 + H2;

4. Ca + O2 → CaO;                                                                   34. P2O5 + H2O → H3PO4;

5. Na + H2O → NaOH + H2;                                                    35. Ag2O + HCl → AgCl2 + H2O;

помогите!! уравнить!!!