The wavelength of the first line of Lyman series for hydrogen atom is equal to that of the second line of Balmer series for a hydrogen-like ion. The atomic number `Z` of hydrogen-like ion is

Options

A. 3
B. 4
C. 1
D. 1

Answer

D

Explanation

The wavelength of the first line of lyman series for hydrogen atom is
`(1)/(lambda) = R [(1)/(1^2)-(1)/(2^2)]`
The wavelength of the second line of Balmer series for hydrogen like ion is
`(1)/(lambda ) = Z^(2) R [(1)/(2^2)-(1)/(4^2)]`
Equate `lambda =lambda` ..