CuSO4 +2KOH = Cu(OH)2↓ + K2SO4
Cu²⁺+SO₄²⁻+2K⁺+2OH⁻ = Cu(OH)₂↓ + 2K⁺+SO₄²⁻
Cu²⁺+2OH⁻=Cu(OH)₂↓
Cu(NO3)2 + H2S = CuS↓ + 2HNO3
Cu²⁺+2NO₃⁻+2H⁺+S²⁻ = CuS↓ +2H⁺+2NO₃⁻
Cu²⁺+S²⁻ = CuS↓
CuSO4 + Ba(OH)2 = Cu(OH)2↓ + BaSO4↓
Cu²⁺+SO₄²⁻+Ba²⁺+2OH⁻ = Cu(OH)₂↓ + BaSO₄↓
Cu(NO3)2 + Ba(OH)2 = Cu(OH)2↓ + Ba(NO3)2
Cu²⁺+2NO₃⁻ + Ba²⁺+2OH⁻ = Cu(OH)₂↓+ Ba²⁺+2NO₃⁻
Cu²⁺+2OH⁻ = Cu(OH)₂↓