Question

Determine wavelength of the radiation emitted, when in a hydrogen atom electron falls from infinity to stationary state 1. (Rydberg constant $=1.097\times {10}^7{m}^{-1}$)

• A. 91 nm
• B. 95 nm
• C. 81 nm
• D. 85 nm

Answer 1

The correct option is A 91 nm

$\frac{1}{\lambda }=R[\frac{1}{n_1^2}-\frac{1}{n_2^2}]$.

$\frac{1}{\lambda }=1.097\times {10}^7\left(\frac{1}{1}\right)$.

$\lambda =\frac{1}{1.097}\times {10}^{-7}m$.

$\lambda =0.91157\times {10}^{-7}m$

or, $\lambda =91nm$