The Bohr model of the hydrogen atom

In 2013 we celebrate the 100th anniversary of Bohr's model of the hydrogen atom in many different ways.

We have prepared teaching material including experiments and professional information, lectures, conferences and also this interactive video poster.

On the poster you will find two QR codes leading to small films about Niels Bohr and also an animation of the visible part of the Balmer series.

  Download the video poster

The animation is in Danish. The following is a translation of the speech as well as references to additional information.


The electron moves at levels of constant energy/stationary states around the atomic nucleus without emitting any energy (light).

The electron never exists between the stationary energy levels.

When energy is provided, e.g. in the form of light (a photon), a precise amount of energy is absorbed and the electron disappears and reappears in a higher energy level

The amount of energy absorbed corresponds ONLY to the energy difference between the two energy levels.

You CANNOT see the electron during the transition between stationary states.

Notice at the bottom right, a black line appears in the spectrum as an absorption line. This is the energy the electron takes so energy/light disappears from the spectrum.

At some time, the electron falls again to the lower energy level. The difference in energy between the two levels is emitted in the form of a photon.

Notice that an energy/light line appears again in the emission spectrum at the lower left.

Links in english:

Erland Andersen