Discussion Forum

A hydrogen atom is in ground state. Then to get six lines in emission spectrurn, wavelength of incident radiation should be

Answer:

Explanation:

Number of possible spectral lines emitted when an electron jumps back to ground state from n^th orbit = $\frac{n(n-1)}{2}$

Here, $\frac{n(n-1)}{2}$ = 6 → n = 4

Wavelength λ from transition from n = 1 to n = 4 given by,

$\frac{1}{\lambda} = R\left(\frac{1}{1}-\frac{1}{4^{2}}\right)$ 

$\Rightarrow\lambda = \frac{16}{15R}= 975 Å$