Balance CuO+NH3=Cu+N2+H2O by using oxidation number method

Dear student


CuO  +  NH3 <===>  Cu + N₂  + H₂O
+2 -2    -3  +3               0       0      +2 -2

This is a acid - base neutralisation reaction.
Reduction -   3Cu^​2+ + 6e^- ----> 3Cu⁰

Oxidation-   2N^3- ----> 2N⁰ +   6e^-

In this reaction, N is oxidised by -3 to 0 and Cu is reduced by +2 to 0 so for balancing the reaction we multiply 3 by CuO and 2 by NH_3. 

The balance chemical reaction is: 3CuO + 2NH3 <===> 3Cu +   N₂  + 3H₂O

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