Given the value of Rydberg constant is `10^(7)m^(-1)`, the waves number of the lest line of the Balmer series in hydrogen spectrum will be:

Options

A. `0.5xx10^7 m^(-1)`
B. `0.25xx10^7 m^(-1)`
C. `2.5xx10^7 m^(-1)`
D. `0.025xx10^5 m^(-1)`

Answer

B

Explanation

`R=10^7 m^(-1)`
For Balmer series for H-spectrum,
Fro last line ,
Wave number =`1/lambda_"min"=R(1/n_1^2-1/n_2^2)`
`=10^7 (1/2^2 -1/oo^2)=0.25xx10^7`