Fractional distillation is the process of extracting a specific element from a mixture by cooling and compressing liquid air until it becomes liquid. In this case, the element is neon.

Neon is the fifth most abundant chemical element in the universe, behind hydrogen, helium, oxygen and carbon. It is a noble gas, meaning that it is stable with a full octet of electrons.

Unlike other gases, neon and the other noble gases do not react with any known chemicals. Its rare nature and low oxidation state allow it to be isolated by bringing liquid air into contact with activated charcoal. The activated charcoal absorbs the neon and hydrogen from the air, isolating it from the other gases.

The elements of the noble group have a lower boiling point than other substances, due to van der waal forces between the atoms. This property is useful in certain applications, such as the creation of vaporized light bulbs in electric discharge tubes and fluorescent lighting devices.

It is also a very good refrigerant, with more than 40 times the refrigeration capacity of liquid helium and three times that of hydrogen on a per unit volume basis. This makes it an attractive choice for a number of applications, such as high-voltage switching gear and diving equipment.

Despite the fact that neon is a very inert element, it can form unstable compounds and weak bonds with other substances under extreme circumstances such as very low temperatures and high pressures. Under these conditions, it forms clathrates or Van der Waals molecules.