Question

how do u do a redox balance of the following reaction : Fe(NH4)2(SO4)2*6H2O + H2C2O4 + K2C2O4 + H2O2 -> K3Fe(C2O4)3*3 H2O + (NH4)2SO4 + H2SO4 +H2O

i only know Fe2+ -> Fe3+ +1e-

Answer 1

The O in the peroxide is -1, but in the product side, all O are -2, so O-1 gains an electron.

Answer 2

Just as an aside here, I believe you have omitted something from the equation (or perhaps you made a typo) BUT there is no Fe on the left and you have Fe on the right. Something is amiss