Chemistry 2: Ionic Bonding

Structure and Bonding - Ionic Bonding

All atoms are trying to achieve a full outer shell. This means that their outer ring of electrons has the highest possible amount of electrons within it. For example, the inner shell of an atom can hold a maximum of 2 electrons. The next shell can hold 8 and 8 again for the shell after that.

Elements try to achieve this by losing, gaining or sharing electrons with other atoms. When atoms lose or gain electrons, it is called Ionic Bonding which normally occurs between metals and non-metals.

Ionic Bonding

In ionic bonding, an element will pass electrons on it's outer shell to an element in need of more electrons. For example, look at the atomic structures of the elements Sodium (Na) and Chlorine (Cl). Atomic structure is the number of electrons in each shell of an element, starting from the inner shell. Remember that an element must fill a shell with electrons in order to start a new one.

Sodium Atomic Structure: 2, 8, 1 Sodium is a group 1 element so has 1 electron on its outer shell

Chlorine Atomic Structure: 2, 8, 7 Chlorine is a group 7 element so has 7 electrons on its outer shell

As Sodium would need 7 more elctrons to complete its outer shell, it is easier for it to get rid of (lose) the 1 outer electron to get a full outer shell. For Chlorine, however, it is easier to gain 1 more electron to fill its outer shell. Here…