1) Al(NO₃)₃ + 3KOH = Al(OH)₃ + 3KNO₃
2Al(OH)₃ = Al₂O₃ + 3H₂O
Al₂O₃ + 2Fe = Fe₂O₃ + 2Al
2) Na₂O + H₂O = 2NaOH
2NaOH + CO₂ = Na₂CO₃ + H₂O
Na₂CO₃ + 2HNO₃ = 2NaNO₃ + H₂O + CO₂
3) 4P + 5O₂ = 2P₂O₅
P₂O₅ + 3H₂O = 2H₃PO₄
H₃PO₄ + 3KOH = K₃PO₄ + 3H₂O
2K₃PO₄ + 3BaCl₂ = Ba₃(PO₄)₂ + 6KCl
4) SO₃ + H₂O = H₂SO₄
H₂SO₄ + Zn = ZnSO₄ + H₂
H₂ + S = H₂S
H₂S + ZnCl₂ = ZnS + 2HCl
5) CuO + 2HCl = CuCl₂ + H₂O
CuCl₂ + 2NaOH = Cu(OH)₂ + 2NaCl
Cu(OH)₂ + 2HNO₃ = Cu(NO₃)₂ + 2H₂O