Question

A hydrogen atom is in its third exited state. (a) How many spectral lines can be emitted by
it before coming to the ground state? Show these transitions in the energy level diagram.
(b) In which of the above transitions will the spectral line of shortest wavelength be
emitted ?
​

Answer 1

1.The no of spectral lines are 3

2.no of spectral lines =(n2-n1)(n2-n1+1)/2

3.n2=3

n1=1

4.no of spectral lines =3

from 2 to 1

the spectral lines will have shortest wave length

Answer 2

A hydrogen atom in which electron goes from third excited stage to ground state will emit number of spectral lines equal to 4*3=12

The energy lost is inversely proportional to the wavelength of spectral line.

Hence the line arising from 3rd excited state to ground state will have the shortest wavelength due to the maximum amount of energy emitted due to the motion from third excited shell to ground state .