For example, imagine that I excite an electron in order to move it to the 19th energy level (when the lowest possible is, let's say, the 2nd (there are three electrons in total in the atom)). How can I know if the electron will tend to move to that n=2 level or if it will leave the atom? What is the highest energy level in which an electron would still tend to move to the lowest state possible?
Thank you in advance. You can add papers, articles etc, as I'm very interested in this topic.