In hydrogen atom the kinetic energy of electron is 3.4 eV. The distance of that electron from the nucleus

Options

A. `2.11 A^@`
B. `0.529 A^@`
C. `1.587A^@`
D. `21.16A^@`

Answer

A

Explanation

3.4 eV is KE .` e^-` in `2^(nd)` orbit
`therefore r = 4(0.529) A^@ = 2.116 A^@`