Air is a homogeneous mixture and can be separated into its components by fractional
distillation. The flow diagram shows the following steps of the process.
If we want oxygen gas from air , we have to separate out all the other gases present in the air. The air is compressed by increasing the pressure and is then cooled by decreasing the temperature to get 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.