Question

In the hydrogen spectrum, which of the following series of lines belongs to the U.V region?
A. Balmer series
B. Paschen series
C. Brackett series
D. Lyman series

Answer 1

Hint: We have to know that the emission spectrum of atomic hydrogen has been split into a number of spectral series. The wavelengths are given by the Rydberg formula. These observed spectral lines are because of the electron making transitions between two energy levels in an atom.

Complete step by step answer:
Let us know that when a photon is absorbed by hydrogen, the electron experiences a transition to a higher energy level. When a photon is released through a hydrogen atom, the electron goes through a transition from a higher energy level to a lower, for example, n=3, n=2. During this transition from a higher level to a lower level, there is the transmission of light.
The Balmer series contains the lines because of transitions from an outer orbit $n > 2$to the orbit \[n' = 2\]. Balmer series is seen in the visible region.
Therefore, the option (A) is incorrect.
Transition takes place from the third shell to any other shell is the Paschen series. The Paschen lines are seen in the near infrared band. This series intersects with the next (Brackett) series.
Therefore, the option (B) is incorrect.
Transition takes place from the fourth shell to any other shell is the Brackett series. The spectral lines of the Brackett series are seen in far infrared bands.
Therefore, the option (C) is incorrect.
The Lyman series contains the lines released by transitions of the electron from an outer orbit of quantum number \[n > 1\] to the 1st orbit of quantum number $n = 1$. All the wavelengths in the Lyman series are seen in the ultraviolet band.
Therefore, the option (D) is correct.

So, the correct answer is Option D.

Note:
We can find the Pfund and Humphrey series in the far infrared region of the electromagnetic spectrum. We can apply the Rydberg formula to any system that contains a single particle orbiting a nucleus such as helium ion.