For the redox reaction
MnO−4+C2O−24+H+⟶Mn2++CO2+H2O
the correct coefficients of the reactants MnO−4, C2O2−4 and H+ for the balanced reaction are
2, 5, 16
Thus the coefficient of MnO−4, C2O2−4, C2O2−4 and H+ in the above balanced equation respectively are 2, 5, 16.