2)
а) Zn + FeSO4 = ZnSO4 + Fe
Zn + Fe²⁺ + SO₄²⁻ = Zn²⁺ + SO₄²⁻ + Fe
Zn + Fe²⁺ = Zn²⁺ + Fe
Zn + 2AgNO₃ = Zn(NO₃)₂ + 2Ag
Zn + 2Ag⁺ + 2NO₃⁻ = Zn²⁺ + 2NO₃⁻ + 2Ag
Zn + 2Ag⁺ = Zn²⁺ + 2Ag
б)
Fe + Pb(NO₃)₂ = Fe(NO₃)₂ + Pb
Fe + Pb²⁺ + 2NO₃⁻ = Fe²⁺ + 2NO₃⁻ + Pb
Fe + Pb²⁺ = Fe²⁺ + Pb
Fe + 2AgNO₃ = Fe(NO₃)₂ + 2Ag
Fe + 2Ag⁺ + 2NO₃⁻ = Fe²⁺ + 2NO₃⁻ + 2Ag
Fe + 2Ag⁺ = Fe²⁺ + 2Ag
в)
Ni + CuSO₄ = NiSO₄ + Cu
Ni + Cu²⁺ + SO₄²⁻ = Ni²⁺ + SO₄²⁻ + Cu
Ni + Cu²⁺ = Ni²⁺ + Cu
Ni + 2AgNO₃ = Ni(NO₃)₂ + 2Ag
Ni + 2Ag⁺ + 2NO₃⁻ = Ni²⁺ + 2NO₃⁻ + 2Ag
Ni + 2Ag⁺ = Ni²⁺ + 2Ag
Ni + Hg(NO₃)₂ = Ni(NO₃)₂ + Hg
Ni + Hg²⁺ + 2NO₃⁻ = Ni²⁺ + 2NO₃⁻ + Hg
Ni + Hg⁺ = Ni²⁺ + Hg