In hydrogen atomic spectrum, a series limit is found at $12186.3 \mathrm{~cm}^{-1}$. Then it belong to
In hydrogen atomic spectrum, a series limit is found at $12186.3 \mathrm{~cm}^{-1}$. Then it belong to
Lyman series
Balmer series
Paschen series
Brackett series
Solution
Series limit is the last line of the series, i.e. $n_{2}=\infty$. $\therefore \bar{v}=\frac{1}{\lambda}=\mathrm{R}\left[\frac{1}{\mathrm{n}_{1}^{2}}-\frac{1}{\mathrm{n}_{2}^{2}}ight]=\mathrm{R}\left[\frac{1}{\mathrm{n}_{1}^{2}}-\frac{1}{\infty^{2}}ight]=\frac{\mathrm{R}}{\mathrm{n}_{1}^{2}}$
$\because \overline{\mathrm{v}}=12186.3=\frac{109677.76}{\mathrm{n}_{1}^{2}}$
$\Rightarrow n_{1}^{2}=\frac{109677.76}{12186.3}=9 \Rightarrow n_{1}=3$
- The line belongs to Paschen series.
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