Ba(NO₃)₂ + H₂SO₄ = 2HNO₃ + BaSO₄
Ba²⁺ + 2NO₃⁻ + 2H⁺ + SO₄²⁻ = 2H⁺ + 2NO₃⁻ + BaSO₄
Ba²⁺ + SO₄²⁻ = BaSO₄
AlCl₃ + 3NaOH = Al(OH)₃↓+3NaCl
Al³⁺ + 3Cl⁻ + 3Na⁺ +3OH⁻ = Al(OH)₃↓ + 3Na⁺ + 3Cl⁻
Al³⁺ + 3OH⁻ = Al(OH)₃↓
Na₂CO₃ + H₂SO₄ = Na₂SO₄ + CO₂↑ + H₂O
2Na⁺ + CO₃²⁻ + 2H⁺ + SO₄²⁻ = 2Na⁺ + SO₄²⁻ + CO₂↑ + H₂O
CO₃²⁻ + 2H⁺ = CO₂↑ + H₂O