According to Bohr's theory of hydrogen atom , the product of the binding energy of the electron in the nth orbit and its radius in the nth orbit

Options

A. is proportional to `n^(2)`
B. is inversely proportional to `n^(3)`
C. has a consatnt valueof `10.2 eV-Å`
D. has a consatnt valueof `7.2 eV-Å`

Answer

D

Explanation

`E_(n) prop (1)/(n^(2))` and `r_(n) prop n^(2)`
Therefoe, `E_(n) r_(n)` is independent of `n` .
Hence, `E_(n) r_(n) = (13.6 eV) (0.53 Å)`
`= 7.2 eV - Å`
`= constant`