Q. Fractional distillation is the separation of a mixture into its component or fractions. This process is based on difference in boiling point of the components in the mixture. This is a special type of distillation.
Air is a homogeneous mixture of 78.09% nitrogen, 20.95% oxygen, 0.93% argon, 0.039% carbon dioxide, and small amounts of other gases such as helium, krypton, nitrogen dioxide etc.
Consider three gases oxygen, nitrogen and argon whose boiling points are: -183, -196, -186 degree celsius. They are to be separated from air using fractional distillation.
Air is compressed by increasing pressure and is then cooled by decreasing the temperature to form liquid air. This liquid air is allowed to warm-up slowly in a fractional distillation column, where gases get separated at different heights depending upon their boiling points. As the height of tower increases the temperature increases.
Among the three gases, which gas is collected at last?
