HC0HO + 2 (AgI(NH3)2)+ + 3 OH- HCIIOO- + 2 Ag0 + 4 NH3 + 2 H2O

This is an oxidation-reduction (redox) reaction:

C0 - 2 e- CII (oxidation)

2 AgI + 2 e- 2 Ag0 (reduction)

Change the oxidation states