The energy of seperation of an electron in a hydrogen like atom in excited state is 3.4eV. The de-Broglie wave length (in Å) associtated with the electron is :

Options

A. 3.33
B. 6.66
C. 13.31
D. None of these

Answer

B

Explanation

`2 pi r_(n) = n lambda rArr 2 pi xx 0.53 (n)/(z) = n lambda`
`lambda = 2pi xx 0.53 xx (n)/(z)" "…..(i)`
`E_("sep") = 3.4 = 13.6 (Z^(2))/(n^(2)) rArr (n)/(z) = 2`
`lambda = 23.14 xx 0.53 xx 2 = 6.66Å`