Q 12.6 A hydrogen atom initially in the ground level absorbs a photon, which excites it to the n = 4 level. Determine the wavelength and frequency of photon.
The initial energy of the electron is E1
E1 =-13.6 eV
The energy of the electron when it is excited to level n=4 is E2
E2=-0.85 eV
The difference between these two energy levels is equal to the energy of the photon absorbed by the electron.
The energy of the photon E = E2 - E1
E = -0.85 -(-13.6)
E = 12.75 eV
The wavelength of the photon can be calculated using relation
hc=1240 eV
The wavelength and frequency of the photon absorbed by the hydrogen atom are 98.6 nm and 3.041015 Hz respectively.