Atoms and molecules are in their ground state when all electrons are at their lowest possible energy level. In general, the energy levels of the entire matter are fully occupied or empty, for if an energy level for electrons is only partially occupied, it is immediately taken up by electrons of another molecule or atom, in general by the atoms involved combining. Atoms and molecules which are not in their ground state are therefore highly reactive, i.e. they are always looking for a chemical reaction partner. In the plasma, many atoms and molecules are not in their ground state but in an excited state, i.e. the electrons are either excited to a higher energy level are completely removed from the atomic shell. In the latter case, the atom or molecule has been transformed to become an ion. umgewandelt. Accordingly, plasma is extremely reactive.