What is the valency of copper?
Dear Student,
Copper has variable valency +1 and +2. Due to variable oxidation state, it is placed in transition elements. When copper is in +2 oxidation state, it is called cupric ion. For example: copper sulfate (CuSO4)
Copper in +1 oxidation state is called cuprous ion. For example: cuprous oxide (Cu2O).
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