Question

How can we obtain different gases from air?

Answer 1

Fractional distillation:-

1. The type of distillation where separation of miscible liquids is been done is called fractional distillation.
2. This process here involves repeated distillations and condensations, and generally the mixture is separated into its component parts.
3. When the mixture is heated at a certain temperature where fractions of the mixture start to vaporize, at that moment the separation happens.

Obtaining different gases from air:-

Converting air into liquid air:

• The conversion of this liquid air from the air is done under high pressure
• The air is compressed at first and then cooled by reducing the temperature, under this high pressure.
• This ultimately results in the formation of liquid air.

Fractional distillation of liquid air:

• The main component of air is Oxygen and Nitrogen.
• The liquid air formed from air, is now passed through the fractional distillation column.
• The liquid air here, is allowed to warm up.
• The fractionating column of the bottom is warmer than the top.
• According to their respective boiling point each gas starts to separate at different temperatures.
• Boiling point of Nitrogen is $-196°\mathrm{C}$ and boiling point of Oxygen is $-183°\mathrm{C}$.
• As a result, through the outlet nitrogen gas will start to escape and it is collected.
• At last the liquid oxygen will get collected in the fractionating column.