Question

Which technique is used to separate the components of liquid air?
(a)- Fractional distillation
(b)- Distillation
(c)- Distillation under reduced pressure
(d)- Evaporation

Answer 1

Hint: Liquid air contains mainly liquefied oxygen and liquefied nitrogen. The components of liquid air are separated by the process whose principle is formations of vapors of the component which is more volatile will be more than the vapors of the less volatile component.

Complete answer:
Fluid air is the air that has cooled into a pale, mobile fluid, at very low temperatures (cryogénic temperatures). It is placed in specialist tanks to thermally isolate it from room temperature (vacuum insulated flasks are often used). Liquid air can quickly absorb heat and return to its gaseous condition. It is also used as a source of nitrogen and oxygen for condensation of other compounds into liquids and/or for solidification.
The components of liquid air are separated by the process whose principle is formations of vapors of the component which is more volatile will be more than the vapors of the less volatile component. So, it is separated by fractional distillation.
Fractional distillation is the separate components or percentages of a mixture. By heating them up to a temperature at which one or more fractions of the mixture are vaporized, chemical compounds are isolated. It splits with distillation.
Because nitrogen and oxygen boiling points are similar together, fractional distillation is also used to isolate liquid air components.

Therefore, the correct answer is an option (a)- Fractional distillation.

Note:
One technical use of the split distilling system is to split crude oil into different useful fractions in the petroleum industry such as petrol, kerosene, fuel oil, lubricating oil, and more.