The hydrogen -like species ` Li^(2+)` is in a spherically symmetric state ` S_1` whth one radisal node . Upon absorbing light the ion undergoes transitoj ot a state ` S_2` has one radial node and its energy is equal to the groun sate energy of hhe hydrogen atom.
The state ` S_1` is :

Options

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

Answer

B

Explanation

For ` s_1` (spherically suymmetrical ) state , number of bnodes =1 ltbRgt ` 1 = n-1`
` :. N=2`
i.e It is ` 2s`
For ` s_2` radial node =1
` E_(s_2) = (- 13.6 xx z^2)/n^2 =E_H` inground state =- 13. 6 ltbr. ` E= (- 13. 6 xx 9)/n^2 rArr n=3` ltbRgt So, statem `S_1` is ` 2s` and ` s_2` is ` 3p`.