Electrolysis of water

The electrolysis of water happens when water (H2O) gets separated into oxygen and hydrogen atoms. In order to do this, energy must be introduced in form of electricity. Usually, this cannot happen on its own. The video below shows this reaction. We connected a 9-volt battery to two wires to supply the energy. The bubbles on the black wire are hydrogen bubbles, and the bubbles on the red wire are oxygen.