Question

A hydrogen atom initially in the ground state absorbs a photon which excites it to the n = 4 level. Estimate the frequency of the photon.

Answer 1

Finding the energy in the n = 4 level

Estimating the frequency of the photon

Energy in the n = 4 level  =  -E₀/4² = E_0/16

Energy required to take the electron from the ground state, to the n = 4 level = (−E_0/16)  - (-E₀)

(Also accept 3 × 1015 Hz)

Detailed Answer :

 We know that ground state energy of hydrogen atom is = – 13.6 eV.

Now if atom is excited to n = 4 level, then we have