Question

When an electron in hydrogen atom is excited from its 3^rd to 5^th stationary orbit, tbe change in angular momentum of electron is (Planck's constant: h = 6.62 x 10-³⁴ Js) ____________.

Options

• 5.26 x 10^-34 Js

• 3.16 x 10^-34 Js

• 1.08 x 10^-34 Js

• 2.11 x 10^-34 Js

Answer 1

When an electron in hydrogen atom is excited from its 3^rd to 5^th stationary orbit, tbe change in angular momentum of electron is 2.11 x 10^-34 Js.

Explanation:

Change in the angular momentum,

`Delta "L" = "L"_2 - "L"_1 = ("n"_2  "h")/(2 pi) - ("n"_1  "h")/(2 pi)`

`therefore Delta "L" = "h"/(2pi) ("n"_2 - "n"_1)`

`= (6.62 xx 10^-34)/(2 xx 3.14) (5 - 3)`

`= 2.11 xx 10^-34  "Js"`