The first emision line of hydrogen atomic spectrum in the Balmer series appear at(R=Rydberg constant)

Options

A. `(5R)/36cm^(-1)`
B. `(3R)/4cm^(-1)`
C. `(7R)/36cm^(-1)`
D. `(9R)/400cm^(-1)`

Answer

a

Explanation

For the first line of hydrogen aton in Balmer series.
`n_1=2,n_2=3`
Consider the equation,
`v=R[1/(n_1^(2))-1/n_2^(2)]`
`=R[1/(2^(2))-1/3^(2)]`
`=R[1/4-1/9]`
`=R[(9-4)/36]`
`(5R)/36cm^(-1)`