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 the photon. 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 the photon. September 13, 2021 Category: Chapter 12 - Atoms , NCERT Exemplar Class 12 , Physics , Facebook Messenger WhatsApp Share this:TwitterFacebook Related