Question

What lines of atomic hydrogen absorption spectrum fall within the wavelength ranges from $94.5$ to $130nm$?

Answer 1

Longest wavelength $=130nm$

$\because \frac{1}{\lambda }=R_h[\frac{1}{n_1^2}-\frac{1}{n_2^2}]n_1=1$

$\because \frac{1}{\lambda }=R_h\left[\frac{n_2^2-1}{n_2^2}\right]⟹\frac{n_2^2-1}{n_2^2}=\frac{1}{130\times {10}^{-9}\times 109678}=0.7$

$\therefore n_2$ is possibly equal to $2$.

This corresponds to Lyman series.

Hence the given lines correspond to Lyman series.