Complete and balance the redox reaction in basic solution

Question

MnO4^-(aq)+C2O4^2-(aq)--->MnO2(s)+CO2(g)

Answer 1

MnO₄^- ==> MnO₂ ... reduction half reaction

MnO₄^- + 4H₂O ==> MnO₂ + 2H₂O + 4OH^- ... balanced for Mn, O, and H in basic solution

MnO₄^- + 4H₂O + 3e- ==> MnO₂ + 2H₂O + 4OH^- ... balanced for Mn, O, and H and charge = balanced eq.

C₂O₄^2- ==> CO₂ ... oxidation half reaction

C₂O₄^2- ==> 2CO₂ + 2e- ... balanced for C, O and charge = balanced eq.

Multiply reduction by 2 and oxidation by 3 to equalize electrons, then add them together to get...

2MnO₄^- + 8H₂O + 6e- + 3C₂O₄^2- ==> 2MnO₂ + 4H₂O + 8OH^- + 6CO₂ + 6e-

which simplifies to:

2MnO₄^- + 4H₂O + 3C₂O₄^2- ==> 2MnO₂ + 8OH^- + 6CO₂ ... BALANCED REDOX EQUATION