[khaoz]

Normally, the electron configuration for copper would be [Ar] 4s¹ 3d¹⁰. What would be the configuartion for a Cu²⁺ stable ion be?

[madscientist]

Cu = [Ar]3d¹⁰4s¹ this configuration does not follow the n+l rule. in other words if you use box notation to map out the electron configuration of Cu²⁺ you dont fill the 4s orbital first.

so,if:Cu=[Ar]3d¹⁰4s¹=29=atomic number=nu-mber of electrons

Then, Cu2+ indicates that 2 electrons have been given up by the copper atom and the electron configuration is therefore:

Cu2+= [Ar]3d⁹ =27= atomic number = number of electrons

[DeP]

For Cu²⁺ you have indeed 27 electrons,
but first you have to fill in the 4s orbital and than the 3d orbital
so then you have  for Cu²⁺ a [Ar]3d⁷4s² electron configuration

The reason that they for Cu⁰ fill in first the 3d orbital instead of the 4s orbital, is because a full 3d orbital is more stable than an incompletely filled 3d orbital

[vmelkon]

For Cu²⁺ you have indeed 27 electrons,
but first you have to fill in the 4s orbital and than the 3d orbital
so then you have  for Cu²⁺ a [Ar]3d⁷4s² electron configuration

The reason that they for Cu⁰ fill in first the 3d orbital instead of the 4s orbital, is because a full 3d orbital is more stable than an incompletely filled 3d orbital

An electron jumps from the 3d to the 4s?