The Balmer series in the hydrogen spectrum corresponds to the transition from n1 = 2 to n2 = 3,4,………. This series lies in the visible region. Calculate the wavenumber of the line associated with the transition in Balmer series when the electron moves to n = 4 orbit. (RH= 109677 cm-1)
The Balmer series in the hydrogen spectrum corresponds to the transition from n1 = 2 to n2 = 3,4,………. This series lies in the visible region. Calculate the wavenumber of the line associated with the transition in Balmer series when the electron moves to n = 4 orbit. (RH= 109677 cm-1)

Calculation:

According to Bohr’s model for the hydrogen atom;

ν = RH(1/n12-1/ n22)cm-1

Given,

n1 = 2

n2 = 4

H (Rydberg’s constant) = 109677

Wave number = 109677 ( ¼-1/16)

Hence, Wave number = 20564.44cm-1