Question

Which of the following involves fractional distillation?
i. Separation of constituents from liquefied air
ii. Separation of constituents from crude petroleum
iii. Separation of carbon tetrachloride from water
iv. Separation of naphthalene from common salt.

• A. i and ii
• B. i and iv
• C. ii and iv
• D. i and iii

Answer 1

The correct option is A i and ii

The fractional distillation method is used to separate components with a very small difference in their boiling point.

Liquefied air and crude petroleum products have a very small difference in their boiling point and can be separated by the fractional distillation method.

Carbon tetrachloride is immiscible with water and forms a separating layer when mixed together. Hence, can be separated by using a separating funnel.

Naphthalene and common salt can be separated by using sublimation. Sublimation involves conversion from solid to gas phase so naphthalene vapors can be collected after sublimation and common salt remains at the bottom.

Hence, option $A$ is correct.