Question

The common charges of an element can be related to the electron configuration of the element. Why would copper ions have two common charges? Explain each of them in terms of the electron configuration.

Answer 1

Copper has 29 electrons. So its electronic configuration should be

1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d⁹

But since if there is a possibility for an orbital to be half filled, the configuration is considered to be more stable.

1s² 2s² 2p⁶ 3s² 3p⁶ 4s¹ 3d¹⁰

Now Copper shows two charges respectively of +1 & +2. This can be clearly visible from above electronic configuration.

For +2 state the resulting config. will be 1s² 2s² 2p⁶ 3s² 3p⁶ 3d⁹

For +1 state the resulting config. will be 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰

Hence copper exists in two different oxidation state