HCl + AgNO₃ = AgCl↓ + HNO₃.
H⁺ + Cl⁻ + Ag⁺ + NO₃⁻ = AgCl↓ + H⁺ + NO₃⁻
Ag⁺ + Cl⁻ = AgCl↓
CuSO₄ + 2KOH = Cu(OH)₂↓ + K₂SO₄
Cu²⁺ + SO₄²⁻ + 2K⁺ + 2OH⁻ = Cu(OH)₂↓ + 2K⁺ + SO₄²⁻
Cu²⁺ + 2OH⁻ = Cu(OH)₂↓
CaCO₃ + 2HCl = CaCl₂ + CO₂↑ + H₂O
CaCO₃ + 2H⁺ + 2Cl⁻ = Ca²⁺ + 2Cl⁻ + CO₂↑ + H₂O
CaCO₃ + 2H⁺ = Ca²⁺ + CO₂↑ + H₂O