Question

The energy of an electron in an excited hydrogen atom is - 3.4 eV. Calculate the angular momentum of the electron according to Bohr's theory. (h = 6.626 × 10^-34 Js)

Answer 1

In Hydrogen atom, the energy of electron in the n^th energy level is,

`"E"_"n" = - 13.6/"n"^2`eV

Here, E_n = - 3.4 eV

`therefore - 3.4 = 13.6/"n"^2`

or, `"n"^2 = 13.6/3.4` = 4

∴ n = 2

According to Bohr's Theory, the angular momentum of the electoms is,

`"nh"/(2pi) = (2 xx 6.626 xx 10^-34)/(2 xx 3.14)`

`= 2.11 xx 10^-34`Js