What are Ions? Well they are simply atoms or molecules that have a charge, where they have less or more electrons than they should.  There are two types of ions, anions and cations. Anions have more electrons than protons, giving them a negative charge  and cations have more protons than electrons, giving them a positive charge. If an ion has unpaired electrons in them, they become very reactive.  An example of an ion is sodium, which reacts violently with water. When combined with chlorine it creates table salt. In fact it is so reactive that it has to be stored in a hydrocarbon (e.g. gasoline, kerosene etc.) otherwise it will explode. .