2KNO3=KNO2+2O2           N^+5 + 2e=N^+3       2

                                     2O^-2 - 4e  =O2^0     1

2Cu(NO3)2=2CuO+4NO2+O2      N^+5  +1e =N^+4     4

                                              2O^-2  -4e =O2^0     1

2AgNO3=2Ag+2NO2+O2

                                            Ag^+1  +1e=Ag^0      +1

                                            N^+5   +1e=N^+4       +1     2

                                            2O^-2   -4e=O2^0      -4     1