When an electrons comes back from fifth orbit to ground state of Hydrogen atom the total number of spectral lines and lines in UV regions are?

Answer :

Number of visible lines when an electron returns from 5th orbit to the ground state in the H spectrum is 10.

The number of spectral lines =

2

n(n−1)

.

The number of spectral lines =

2

5(5−1)

=10.

These lines belong to the UV region.

Note: Lyman series corresponds to transitions to n=1 level.

Thanks