Answer:
[tex]1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^2[/tex]
Explanation:
The [tex]Mn^{+3}[/tex] has 22 electrons arround the nucleous. Its ground state configuration following the diagonal rule is:
[tex]1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^2[/tex]
In term of the previous noble gas:
[tex][Ar] 4s^2 3d^2[/tex]