Ionic Bonding

Ionic bonding occurs between a metal and non-metal atom and involves the transfer of electrons.
The atom losing electrons becomes a positive ion (cation) and the atom gaining electrons becomes a negative ion (anion).
This transfer of electrons allows both atoms to achieve stable electron configurations, generally with outer shells filled to their capacity.
The force of attraction between the oppositely charged ions is known as the ionic bond.

Structure and Properties of Ionic Compounds

Ionic compounds form giant ionic lattices - repeating three-dimensional structures of positive and negative ions.
They have high melting and boiling points due to the strong electrostatic forces of attraction between the positive and negative ions. These forces require a high amount of energy to overcome.
When in liquid state (melted) or dissolved in water, ionic compounds conduct electricity. This is because their ions are free to move and can carry the electrical charge.

Table salt or sodium chloride (NaCl) is a classic example of an ionic compound, formed by the transfer of an electron from sodium to chlorine.
Another example is magnesium oxide (MgO), formed when magnesium donates two electrons to oxygen.

Ionic equations are used to represent the ions involved in a chemical reaction.
Ions that do not participate in the reaction are called spectator ions, these are not included in the simplified ionic equation.

Ionic bonds hold the ions together in a regular lattice structure, and it is the loss and gain of electrons which create the oppositely charged ions.
An understanding of the periodic table and the electron configurations of atoms is key to understanding what ions will form in an ionic bond.