The two half-reactions are... Ag→Ag+ and... NO3→NO Let's start by balancing the first half-reaction... Ag→Ag+ The amounts are already balanced; 1:1. The oxygens are balanced. So all that's left is to balance the charge... Ag→Ag++e− Now let's do the other equation... Amounts of nitrogen are balanced, so we first need to balance the oxygens... NO3→NO 4H++NO3→NO+2H2O Next, we need to balance charge... 4e−+4H++NO3→NO+2H2O Now let's go ahead and rewrite each half-reaction after being balanced by themselves... Ag→Ag++e− 4e−+4H++NO3→NO+2H2O Now we need to multiply by some factor to get the electrons to cancel out. In this case, that factor is 4, which needs to be applied to the top half-reaction... 4(Ag→Ag++e−)=4Ag→4Ag++4e− Then we combine this half-reaction with the second one above to get... 4Ag+4H++NO3→4Ag++NO+2H2O
