Question

If $\lambda_{\text{max}}$ is 6563 Å, then wave length of second line for Balmer series will be.

• A. $\lambda = \frac{16}{3R}$
• B. $\lambda = \frac{36}{5R}$
• C. $\lambda = \frac{4}{3R}$
• D. None of the above

Answer 1

Answer: (A)

$\lambda = \frac{16}{3R}$

Answer 2

For Balmer series $\frac{1}{\lambda} = R\left( \frac{1}{2^{2}} - \frac{1}{n^{2}} \right)$ where n = 3, 4, 5

For second line n = 4

So $\frac{1}{\lambda} = R\left( \frac{1}{2^{2}} - \frac{1}{4^{2}} \right) = \frac{3}{16}R \Rightarrow \lambda = \frac{16}{3R}$.