KOH + AlCl3 → Al(OH)3 + KCl 7. CH4 + O2 → CO2 + H2O; 2. FeO + HCl → FeCl2 + H2; 8. P2O5 + H2O → H3PO4; 3. Ag2O + HCl → AgCl2 + H2O; 9. Na2O + CO2 → Na2CO3; 4. KClO3 → KCl + O2; 10. HClO3 → HCl + O2; 5. Mg + N2 → Mg3N2; 11. Mg(OH)2 → MgO + H2O 6. H2O + SO3 → H2SO4; 12. CaCO3 → CaO + CO2;