Question

Write the different types of Hydrogen Spectral series. The Lyman series of Hydrogen spectrum lies in the ultraviolet region. Why?

Answer 1

Hydrogen spectral lines:

1. Lyman series ($n=1$)

2. Balmer series ($n=2$)

3. Paschen series ($n=3$)

4. Brackett series ($n=4$)

5. Pfund series ($n=5$)

Where $n$ corresponds to final energy level in the following equation:

$\frac{1}{\lambda }=RZ(\frac{1}{n^2}-\frac{1}{m^2})$

where, $\lambda$ is wavelength

$R$ is Rydberg constant

$Z$ is atomic number

$m$ is initial energy level

From the above equation, in Lyman series longest wavelength corresponding to $m=2$ is 121.57nm and shortest wavelength corresponding to $m=\infty$ is 91.18nm. Therefore, the entire range of Lyman series lies in ultraviolet region.