Question

If the shortest wavelength of H-atom in Balmer series is 'x', then longest wavelength in Paschen series of He is
1) 9x/7
2) 3x/7
3) x/9
4) x/4

Answer 1

-answer is.

9x/7

alpha (Hα) is a specific deep-red visible spectral line in the Balmer series with a wavelength of 656.28 nm in air; it occurs when a hydrogen electron falls from its third to second lowest energy level.