Why does hydrogen have more emission lines than absorption lines?
Jenkin writes: There are, in fact the same number of emission and absorption lines. An emission line is produced when an atom emits a photon of radiation. Energy from some source has promoted an electron to a higher energy level; the electron then emits radiation when it returns to a lower energy level. The frequency of the line corresponds to the difference in energy of the two levels. An absorption line is produced when an electron absorbs a photon of energy from external source. Only photons with energy corresponding to the difference between electronic energy levels will be absorbed, and so lines with frequencies corresponding to these differences will be seen. These lines will appear as an absence of radiation of their particular frequencies. Risk assessment Before attempting any practical work based on the advice and suggestions on this website, you must do the following. Identify any hazards, assess the risks from these hazards, and then decide appropriate control measures to re
