Question

why does oxygen have three atoms in copper carbonate (CuC03), although the valency of copper is two

Answer 1

Answer:

because

Explanation:

in reaction 3oxygen molecules are used

Answer 2

it's not only oxyzen, it is copper carbonate and we term carbonate as CO3, it is a compound not only oxygen....

Carbonate, any member of two classes of chemical compounds derived from carbonic acid or carbon dioxide (q.v.).

Explanation:

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