K2Cr2O7+H2SO4+NaNO2=Cr2(SO4)3+NaNO3+K2SO4+H2O ионно-молекулярная форма

Cr₂O₇²⁻+14H⁺+6e=2Cr³⁺+7H₂O   |1
NO₂⁻+H₂O-2e=NO₃⁻+2H⁺          | 3
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Cr₂O₇²⁻+14H⁺+3NO₂⁻+3H₂O=2Cr³⁺+7H₂O+3NO₃⁻+6H⁺   
Cr₂O₇²⁻+8H⁺+3NO₂⁻+=2Cr³⁺+4H₂O+3NO₃⁻
K₂Cr₂O₇+4H₂SO₄+3NaNO₂=Cr₂(SO₄)₃+3NaNO₃+K₂SO₄+4H₂O