Maximum unpaired electrons in an atom

[xiphoid]

Homework Statement

If there are 13 electrons in M shell and one electron in N shell, the the number of unpaired electrons in such atom will be

Homework Equations

M- shell N- shell

The Attempt at a Solution

The configuration should be
3s2 3p6 3d5 4s1
hence the answer should be 6

 

[AGNuke]

Yup, that's the configuration of Chromium.