2 [Cr(NH2CONH2)6]3[Cr(CN)6]2 + 137 K2Cr2O7 + 515 H2SO4 → 89 K2SO4 + 96 KNO3 + 142 Cr2(SO4)3 + 60 CO2 + 587 H2O
This is an oxidation-reduction (redox) reaction:
24 CII - 48 e- → 24 CIV (oxidation)
96 N-III - 768 e- → 96 NV (oxidation)
6 CrII - 6 e- → 6 CrIII (oxidation)
274 CrVI + 822 e- → 274 CrIII (reduction)