All atoms are electrically neutral even though they are comprised of charged, subatomic particles.
The oxidation state and oxidation number of an atom or ion is simply defined as the sum of the negative and positive charges in an atom or ion. Since every atom contains equal numbers of positive and negative charges, the oxidation state or oxidation number of any atom is always zero. This is illustrated by simply totaling the opposite charges of the atoms as shown by the following examples. The transfer of electrons between the atoms of these elements results in drastic changes to the elements involved. This is due to the formation of ionic compounds .