Question

How can we obtain different gases from air

Answer 1

By increasing the pressure, the air can be compressed. The compressed air is allowed to cool by decreasing its temperature and the air gets liquefied. The liquefied air is allowed to pass into a fractional distillation column. Depending upon their boiling point different gases get separated at different heights.

Answer 2

Air is a homogeneous mixture and can be separated into its components by fractional distillation. The flow diagram given under shows the steps of the process. If we want oxygen gas from air, we have to separate out all the other gases present in the air.