IONIC BOND

Ionic Bonds

An ionic bond is formed by the attraction of oppositely charged atoms or groups of atoms. When an atom (or group of atoms) gains or loses one or more electrons, it forms an ion. Ions have either a net positive or net negative charge. Positively charged ions are attracted to the negatively charged 'cathode' in an electric field and are called cations. Anions are negatively charged ions named as a result of their attraction to the positive 'anode' in an electric field.

Every ionic chemical bond is made up of at least one cation and one anion.

Ionic bonding is typically described to students as being the outcome of the transfer of electron(s) between two dissimilar atoms. The Lewis structure below illustrates this concept.

For binary atomic systems, ionic bonding typically occurs between one metallic atom and one nonmetallic atom. The electronegativity difference between the highly electronegative nonmetal atom and the metal atom indicates the potential for electron transfer.

Sodium chloride (NaCl) is the classic example of ionic bonding. Ionic bonding is not isolated to simple binary systems, however.