№1.
а) NaOH + HCl = NaCl + H₂O
Na⁺ + OH⁻ + H⁺ + Cl⁻ = Na⁺ + Cl⁻ + H₂O
OH⁻ + H⁺ = H₂O.
б) ZnO + H₂SO₄ = ZnSO₄ + H₂O
ZnO + 2H⁺ + SO₄²⁻ = Zn²⁻ + SO₄²⁻ + H₂O
ZnO + 2H⁺ = Zn²⁻ + H₂O
в) Ba + 2HCl = BaCl₂ + H₂↑
Ba⁰ + 2H⁺ + 2Cl⁻ = Ba²⁺ + 2Cl⁻ + H₂⁰↑
Ba⁰ + 2H⁺ = Ba²⁺ + H₂⁰↑
г) Na₂CO₃ + CaCl₂ = 2NaCl + CaCO₃↓
2Na⁺ + CO₃²⁻ + Ca²⁺ + 2Cl⁻ = 2Na⁺ + 2Cl⁻ + CaCO₃↓
CO₃²⁻ + Ca²⁺ = CaCO₃↓
№2.
а) Ba → BaO
2Ba + O₂ = 2BaO
б) NaOH → NaNO₃
NaOH + HNO₃ = NaNO₃ + H₂O
№3.
а) K₂S + Fe(NO₃)₂ = FeS↓ + 2KNO₃
2K⁺ + S²⁻ + Fe²⁺ + 2NO₃⁻ = FeS↓ + 2K⁺ + 2NO₃⁻
S²⁻ + Fe²⁺ = FeS↓
б) BaCO₃ + 2HCl = BaCl₂ + CO₂↑ + H₂O
BaCO₃ + 2H⁺ + 2Cl⁻ = Ba²⁺ + 2Cl⁻ + CO₂↑ + H₂O
BaCO₃ + 2H⁺ = Ba²⁺ + CO₂↑ + H₂O
в) 2NaOH + CO₂ = Na₂CO₃ + H₂O
2Na⁺ + 2OH⁻ + CO₂ = 2Na⁺ + CO₃²⁻ + H₂O
2OH⁻ + CO₂ = CO₃²⁻ + H₂O
г) Mg + 2HCl = MgCl₂ + H₂↑
Mg⁰ + 2H⁺ + 2Cl⁻ = Mg²⁺ + 2Cl⁻ + H₂↑
Mg⁰ + 2H⁺ = Mg²⁺ + H₂↑