|A) shaking with caustic soda solution||B) shaking with water|
|C) fractional distillation of liquid air||D) passing air over heated magnesium|
The two main components of air are nitrogen and oxygen. They are seperated by the fractional distillation of liquid air. Liquefied air contains liquid nitrogen and liquid oxygen. Liquid nitrogen with the lower boiling point more readily evaporates than the less volatile liquid oxygen.