the radius of which of the following orbit is same as that of the first Bohr's orbit of hydrogen atom?

Options

A. `He^(+) (n =2)`
B. `Li^(2+) (n =2)`
C. `Li^(2+) (n = 3)`
D. `Be^(3+) (n = 2)`

Answer

D

Explanation

`r_(n) = (0.529 n^(2))/(Z) Å`
`:. r_(1) (H) = (0.520 xx 1^(2))/(1) = 0.529 Å`
`r_(2) (Be^(3+)) = (0.520 xx 2^(2))/(4) = 0.529 Å`