Write down elerctronic fonfigureation of the following and reprot no. of unpaired electron in each .
(a) ` Mn^(2+)`
(b) ` Cr^(2+)`.

Explanation

Electronic configuration No. of unpaired (e )
(a) `._(25 ) Mn^(4 +) : 1 s^2 2s^2 2p^6 3s^6 3d^3 3`
(b) ` ._(24) Cr^(2+) : 1 s^2 2s^2 2p^6 3s^6 3d^4 4`
Note : In case of writing electrinc configuration of cation first write configuration of neutral atom and then take out desired electrons from outer most shell , e.g.,
`._(25)Mn : 1s^2 , 2s^2 , 2p^2, 3s^2 3p^6 3d^5 , 4s^2`
` ._(25) Mn^+ : 1s^2 , 2s^2 , 2p^2, 3s^2 3p^6 3d^5 , 4s^1` .