What is the wavelength of light emitted when the electron in a hydrogen atom undergoes transition from an energy level with n = 4 to an energy level with n = 2?


By referring to Balmer Formula:

We know that


Wave Number


Here n1 = 2 and n2 = 4 and the value of Rh = 109678


Wave Number


= [109678×3] / 16


= 329034 / 16


= 20564.625 cm-1


We know that Wave Number = [1] / [Wavelength, λ]


Therefore, Wavelength = [1 / 20564.625]


λ = 4.863× 10-5 cm


Therefore, the wavelength of the light is 4.86× 10-5 cm


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