Question

The absorption transition between the first and the fourth energy states of hydrogen atom are $3$. The number of emission transitions between these states will be

• A. $3$
• B. $4$
• C. $5$
• D. $6$

Answer 1

The correct option is D $6$

The number of emission transition when an electron is excited from ground state to $n^{th}$ state is given by :-

$N_E=\frac{n(n-1)}{2}$

Here, $n=4$

$\Rightarrow N_E=\frac{4(4-1)}{2}=6$

Hence, option $\left(D\right)$ is correct.

Why this question? This question is based on absorption and emission spectrum lines.