The hydrogen-like species `Li^(2+)` is in a spherically symmetric state `S_1` with one radial node. Upon absorbing light, the ion undergoes a transition to the state `S_2. " The state " S_2` has one radial node and its energy is equal to the ground state energy of the hydrogen atom.
The state `S_1` is

Options

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

Answer

D

Explanation

`(S_1)` is the initial spherically symmetrical state with one radial node=2s. `(S_2) 2p` has no radial node, it must be 3p with one radial node.
`( E ) = -13*6 ((3)^2)/((3)^2)=-13*6 ev =(E_1)_H`
`S_1` is a 2a orbital.