Question

The boiling points of some gases found in the air are given below.

Name	Boiling point($^{\circ }\text{C}$
Krypton	-152
Neon	-246
Nitrogen	-196
oxygen	-183

If a liquid mixture of the above gases is fractionally distilled, in what order will these gases distil out?

Answer 1

Hint: Fractional distillation is based on the process of the difference in the boiling of the substances present in the mixture. The substances having the lower boiling point will be distilled first and thus, the substances having lower point, will be distilled out in the last.

Complete step by step solution:
-By fractional distillation we mean the chemical process of separating the mixture( consisting of a large number of substances, compounds and elements all together) into its constituents’ substances.
-In the fractional distillation, process boiling point plays a very important role. The boiling point of any substance is the temperature at which any substance changes into its vapour phase. The one having the lower boiling point will distil out first. so, among the given gases, the gas having the lower boiling point will distil out. So, we can see that the neon has the lowest boiling point of all and will distil out first, followed by krypton, then nitrogen and at the last oxygen will be distilled out.
-So, the order of the gases in which they will get distilled out is:
Neon >Krypton> nitrogen >oxygen.

Note: Fractional distillation is mostly used for only those mixtures of substances in which the substances have not much difference in their boiling points and cannot be separated through any other means.