Question

How many unpaired electrons in cu+4?

Answer 1

There are three unpaired electrons.

Explanation:

I don't think that copper exists naturally in the +4 oxidation state.

However, it is theoretically possible to generate a `"Cu"^"4+"` ion in the gaseous phase.

The electron configuration of copper is

`"Cu = [Ar] 4s 3d"^10`

For a +4 ion, we remove the `"4s"` electron and three of the `"3d"` electrons.

So, the electron configuration of the ion is

`"Cu"^"4+" = "[Ar] 3d"^7`

The electron configuration diagram becomes

(Adapted from http://galleryhip.com/electron-configuration-diagram.html)

Thus, there are three unpaired electrons.