Cobalt is a Transition Element and it has a partially filled d-orbital. As given it has atomic number 27. In neutral state Cobalt has 27 electrons. These electrons are filled in following order,
1s², 2s², 2p⁶, 3s², 3p⁶, 4s², 3d⁷
Or it can also be written as,
[Ar] 4s², 3d⁷
Where; [Ar] is Argon with electronic configuration 1s², 2s², 2p⁶, 3s², 3p⁶.
