The engergy of separation of an electron in a Hydrogen like atom in excited state is 3.4 eV. The de-Broglie wave length (in `A^@`) associated with the electron is:

Options

A. 3.33
B. 6.66
C. 13.31
D. 16.65

Answer

B

Explanation

3.4 eV `= E_(oo) - E_n = - Z^2 .(13.6) [1/(n_(oo)^2) - 1/(n_n^2)]`
`implies Z = 1 implies lambda = (2pir)/(n) = 6.66 A^@`