Mg+HNO3=Mg(NO3)2+H2O+N2O
Mg + 4HNO3 = Mg(NO3)2 + 2H2O + 2NO2 Mg (c.o. 0) -2 e→ Mg (c.o. +2) |1 N (c.o. +5) +1 e → N (c.o. +4) |2