# Write the complete balanced equation of CuO + NH3 → Cu + N2 + H2​O

3CuO(s) + 2NH3(g) → 3Cu(s) + N2(g) + 3H2O(l).

Hence, oxidation state of the reactant atoms are as follows.

Cu = +2, O = -2, N = -3, H = +1

Oxidation state of the product atoms are as follows.

Cu = 0, N2 = 0, H = +1, O = -2

Therefore, balancing the given equation by oxidation method is as follows.

3CuO(s) + 2NH3(g) → 3Cu(s) + N2(g) + 3H2O(l).