What are the electronic configurations of copper metal, and copper ions?
Not only is it possible, it is likely.
The abridged electronic configuration of copper is,
Copper can lose both 4s electrons creating a +2 charge.
The electron configuration of Copper is
When copper has a +1 charge one of the 4s electrons is moved to a slightly higher energy state of the 3d. When one of the 4s electrons is moved to the 3d sub orbitals there are 10 3d electrons completely filling the 3d sub orbitals, making it more stable. as the 3d orbitals sink down to the third energy level.
In a similar manner the
Copper becomes a + 2 ion by losing both of the 4s electrons. Losing the two 4s electrons makes copper more stable.