An electron in a Hydrogen atom is in energy level n=7 and drops down into the ground state (n=1). What is the energy of the photon that is emitted in units of eV?

An electron in a hydrogen atom makes a transition from the first excited state to n = 5. Find the frequency and wavelength of the photon involved in this transition. Is the photon emitted or absorbed? Explain your answer.

Electrically excited mercury atoms have particularly strong emission of 4.9 eV photons, corresponding to a transition of one of the atom’s electrons from a higher energy state to a lower. Mercury vapor absorbs light of this wavelength as well; the energy of the photon moves an electron from the lower state to the higher.It’s also possible to produce an excitation through other means. If an electron with a kinetic energy of 4.9 eV strikes a mercury atom, it can transfer energy, moving an electron in the mercury atom from the lower level to the higher. The electron loses kinetic energy in the process; this is an inelastic collision. Electrons with kinetic energies lower than this transition energy undergo elastic collisions, leaving their kinetic energy unchanged.This was the idea behind the Franck-Hertz experiment, a classic experiment of early-20th-century physics. The basic setup is illustrated in Figure P28.88a. A tube is filled with mercury vapor. A heated electrode emits…

An electron in a Hydrogen atom is in energy level n=5 and drops down into the n=2 level. What is the wavelength of the photon that is emitted in units of nm.