to solve this half-reaction method, we divide the reaction into two equations- reduction and oxidation side. The oxidation is simply Ag= Ag+ + e-. The reduction side is 4H+ + NO3-+e-=NO+2H20. H2O is used to balance O and H+ is used to balance H. Hence the final equation is Ag+4H+ + NO3-= NO+2H2O.
