Question

The wavelength of the radiation emitted , when in a hydrogen atom electron falls from infinity to stationary state 1 , would be :
(Rydberg constant = `1.097 xx 10^(7) m^(-1)`)
A. 409 nm
B. 192 nm
C. 91 nm
D. `9.1 xx 10^(-8)` nm

Answer 1

Correct Answer - C
`1/lambda=R[1/n_1^2-1/n_2^2]`
`1/lambda=1.097xx10^7 m^(-1) [1/1^2 -1/oo^2]`
`therefore lambda=91xx10^(-9) m`
We know `10^(-9)` =1 nm So `lambda`=91 nm