If the wavelength of the first line of the Balmer series of hydrogen atom is `656.1` `nm ` the wavelngth of the second line of this series would be

Options

A. `218.7 nm`
B. `328.0 nm`
C. `486.0 nm`
D. 640.0 nm

Answer

C

Explanation

( c) `(1)/(lamda_1) = R_H ((1)/(2^2) -(1)/(3^2)) = R_H ((5)/(36))`
`R_H = (36)/(5 xx 656.1)`
`(1)/(lamda_2)= R_H ((1)/(2^2) -(1)/(4^2))`
`(1)/(lamda_2) = (36)/(5 xx 656.1) ((3)/(16))`
`lamda = (5 xx 656.1 xx 16)/(3 xx 36) = 486.0 nm`.