<span>5H2SO4 + 8KI = 4I2 + H2S + 4K2SO4 + 4H2O
S⁺⁶ + 8 e = S⁻² |1
2I⁻¹ - 2e = I₂⁰ | 4
</span>
<span>S⁺⁶ - окислитель
</span><span>I⁻¹ - восстановитель </span>
А.
CuSO₄ + 2KOH = Cu(OH)₂ + K₂SO₄
Cu²⁺ + SO₄²⁻ + 2K⁺ + 2OH⁻ = Cu(OH)₂ + 2K⁺ + SO₄²⁻
Cu²⁺ + 2OH⁻ = Cu(OH)₂
Б.Cu(OH)₂ + 2HCl = CuCl₂ + 2H₂O
Cu(OH)₂ + 2H⁺ + 2Cl⁻ = Cu²⁺ + 2Cl⁻ + 2H₂O
Cu(OH)₂ + 2H⁺ = Cu²⁺ + 2H₂O
В.
Na₂CO₃ + BaCI₂ = 2NaCI + BaCO₃
2Na⁺ + CO₃²⁻ + Ba²⁺ + 2CI⁻ = 2Na⁺ + 2CI⁻ + BaCO₃
Ba²⁺ + CO₃²⁻ = BaCO₃
Г.NaOH + HNO₃ = NaNO₃ + H₂O
Na⁺ + OH⁻ + H⁺ + NO₃⁻ = Na⁺ + NO₃⁻ + H₂O
<span>OH</span>⁻ + H⁺ = H₂O
CH3-CH=CH-CH3 + H2O = CH3-CHOH-CH2-CH3
Над углеродом ставь -2
над водородом +1