Emission spectra

An atom can be excited from a lower energy level to a higher energy level by acquiring energy from an electrical discharge. When the atom moves back to a lower energy level, it emits energy in the form of electromagnetic radiation. Since an atom has a specific set of energy levels, exact amounts of energy are released when atoms fall to lower energy levels. When the wavelengths of emitted light are separated using a spectroscope, lines may be seen in the visible region of light that correspond to these transitions.

Question 2: The emission spectrum of hydrogen is shown below. The indigo line at 434 nm corresponds to the energy difference between the n = 2 energy level and the n = 5 energy level. When the atom emits this energy, is it a) going from n = 2 to n = 5, or b) going from n = 5 to n = 2? Answer