Which state of triply ionised beryllium `(Be^(+++))` has the same orbital radius as that of the ground state of hydrogen?

Options

A. `n=3`
B. `n=4`
C. `n=1`
D. `n=2`

Answer

D

Explanation

Radius of orbit =`(epsilon_(0)h^(2)n^(2))/(pimZe^(2))`
`therefore`   `rpropn^(2)//Z`
As radius of hydrogen in ground state is equal to state of triply ionised beryllium.
`rArr`   `(1^(2))/(1)=(n^(2))/(4)`[ a tomic number of Be = 4]
n=2