Question

The energy of an electron in an orbit in hydrogen atom is −3.4 eV. Its angular momentum in the orbit will be ______.

Options

• `(3 h)/(2 pi)`

• `(2 h)/pi`

• `h/pi`

• `h/(2 pi)`

Answer 1

The energy of an electron in an orbit in hydrogen atom is −3.4 eV. Its angular momentum in the orbit will be `bbunderline(h/pi)`.

Explanation:

Given: E = −3.4 eV

In the Bohr model of the hydrogen atom:

Energy of n^th orbit (E_n) = `-13.6/n^2` eV

−3.4 = `-13.6/n^2`

n² = `13.6/3.4`

n² = 4

n = 2

L = `(n h)/(2 pi)`

= `(2 h)/(2 pi)`

= `h/pi`