Changes in Energy

An absorption transition, unlike an emission transition is created by starting with a lower energy level (largest negative energy value) and ending with a higher energy level (smallest negative energy value). Notice that the arrows that represent the allowed transitions point upward to represent that the hydrogen gas absorbs these energies emitted by the light source. As a result, electrons acquire enough energy (equal to the difference of the allowed total energies) to move up to the higher allowed energies.