Energy level diagram for the hydrogen atom and explanation of the different series of spectral lines for hydrogen:

 Energy level diagram for the hydrogen atom and explanation of the different series of spectral lines for hydrogen:

According to Bohr's model of the hydrogen atom, an atom exists most of the time in one of a number of stable and discrete energy states. The various states arranged in order of increasing energy constitute the energy level diagram of the atom, as shown in Fig. 154 for the hydrogen atom. Here, the higher (less negative) energies are at the top while the lower (more negative) energies are toward the bottom.

According to Bohr's theory, electromagnetic radiation of a particular wavelength is emitted when there is a transition of the electron from a higher energy state to a lower energy state. Let the quantum number n= m represent a higher energy state and n=n represent a lower energy state (m> n). The formation of the different series of spectral lines is explained from the energy level diagram.