The ground state energy of hydrogen atom is `-13.6 eV`. If an electron makes a transition from an energy level `-0.85 eV to -1.51 eV`, Calculate the wavelength of the spectral line emitted. To which series of hydrogen spectrum does this wavelength belong?

Explanation

Here `Delta E = E_(2) - E_(1) = -0.85 - (-1.51)`
` = 0.66 eV`
`Delta E = 0.66 xx 1.6 xx 10^(-19)`J
` lambda = (he)/(Delta E) = (6.63 xx 10^(-34) xx 3 xx 10^(8))/(0.66 xx 1.6 xx 10^(-19))`
` = 18.84 xx 10^(-7)`
`lambda = 18840 Å`
This wavelength belongs to the Pachen series of the hydrogen spectrum.