The electronic configuration of an element with the largest difference between the `1^(st) and 2^(nd)` ionization energies is

Options

A. `1s^2 2s^2 2p^6`
B. `1s^2 2s^2 2p^6 3s^1`
C. `1s^2 2s^2 2p^6 3s^2`
D. `1s^2 2s^2 2p^1`

Answer

B

Explanation

Largest difference between `1st and 2nd ` IE
Abnormal jump in I. E. is normally observed when we break into an inner shell
Hence for
`m larr 1s^2 2s^2 2p^6 3s^1 to IE`

(Electron to be removed from 2p )
Hence `IE_2 gt gt IE_1`.