FeSO₄ + 2NaOH = Fe(OH)₂↓ + Na₂SO₄;
Fe²⁺ + SO₄²⁻ + 2Na⁺ + 2OH⁻ = Fe(OH)₂↓ + 2Na⁺ + SO₄²⁻;
Fe²⁺ + 2OH⁻ = Fe(OH)₂↓.
BaCl₂ + H₂SO₄ = BaSO₄↓ + 2HCl;
Ba²⁺ + 2Cl⁻ + 2H⁺ + SO₄²⁻ = BaSO₄↓ + 2H⁺ + 2Cl⁻;
Ba²⁺ + SO₄²⁻ = BaSO₄↓.
AgNO₃ + HCl = AgCl↓ + HNO₃;
Ag⁺ + NO₃⁻ + H⁺ + Cl⁻ = AgCl↓ + H⁺ + NO₃⁻;
Ag⁺ + Cl⁻ = AgCl↓.
Zn + 2HCl = ZnCl₂ + H₂↑;
Zn⁰ + 2H⁺ + 2Cl⁻ = Zn²⁺ + 2Cl⁻ + H₂↑;
Zn⁰ + 2H⁺ = Zn²⁺ + H₂↑.
MgO + 2HNO₃ = Mg(NO₃)₂ + H₂O;
MgO + 2H⁺ + 2NO₃⁻ = Mg²⁺ + 2NO₃⁻ + H₂O;
MgO + 2H⁺ = Mg²⁺ + H₂O.