Question

Cr₂O₇^2- + C₂H₄O^- → C₂H₄O₂ + Cr³⁺ in acid solution by ion electron method.

Answer 1

Cr₂O₇^2- + C₂H₂O^- → C₂H₂O + Cr³⁺  ...(i)

Here Cr₂O₇^2- → 2Cr³⁺

i.e., Cr₂O₇^2- → 2Cr³⁺ + 7H₂O

6e^- + 14H⁺ + Cr₂O₇^2- → 2Cr³⁺ + 7H₂O

[H₂O + C₂H₄O^- → C₂H₄O₂ + 2H⁺ + 3e^-] x 2    ...(ii)

10H⁺ + Cr2O₇^2- + 2C₂H₄O^- → 2C₂H₄O₂ + 2Cr³⁺ + 5H₂O