The total energy of `H_(2)` atom, when the electron is in the second quantum state is `E_(2)`. The total energy of `He^(+)` ion in the third quantum state is :

Options

A. `(3)/(2)E_(2)`
B. `(2)/(3)E_(2)`
C. `(4)/(9)E_(2)`
D. `(16)/(9)E_(2)`.

Answer

D

Explanation

`E_(2)(H)=(E_(1)(H))/(2^(2)) :. E_(1)(H)=4E_(2)(H)`
`E_(3)(He^(+))=(Z^(2)E_(1)(H))/(2^(2))`