Question

In a collection of H atom, electrons make a transition from 5th excited state to 2nd excited state, then the maximum number of different types of photons observed are:

• A. 3
• B. 4
• C. 6
• D. 15

Answer 1

Answer: (C)

6

Maximum number of lines are given by formula:
Number of lines =$\frac{(n_2-n_1)(n_2-n_1+1)}{2}$

Here $n_2=6$ and $n_1=3$

Number of lines = $\frac{(6-3)(6-3+1)}{2}=6$

These lines are $6\to 3$, $6\to 4$, $6\to 5$, $5\to 3$, $5\to 4$, $4\to 3$.

Hence, option $C$ is correct.