Spectrum of the hydrogen atom

If the electron goes from the state Ek to En, when k>n, a quantum of radiation is emitted with an energy equal to the energy difference of these levels.

$$ E = \frac{m_e \cdot e^4} {8 \cdot \epsilon_0^2 \cdot h^2} \cdot \left(\frac{1} {n^2} - \frac{1} {k^2} \right) $$

The frequency of the radiation is given by the formula E=hf Due to the quantization of energy, the radiation is discontinuous and forms a so-called series of lines.
 * The Lyman series lies in the ultraviolet part of the spectrum and corresponds to the transition of electrons to the basic energy level n=1.
 * The Balmer series is a transition to n=2 and is in the visible part of the spectrum. Other series (n=3, etc.) are in the infrared part of the spectrum.

Source

 * KUBATOVA, Senta. Biophoto  [online]. [feeling. 2011-01-31]. .