Question

Assertion: The constituents of petroleum can be separated using fractional distillation.
Reason: Fractional distillation is a method of separating heterogeneous liquid mixtures.
(A) Both Assertion and Reason are correct and Reason is the correct explanation for Assertion.
(B) Both Assertion and Reason are correct but Reason is not the correct explanation for
Assertion.
(C) Assertion is correct but Reason is incorrect.
(D) Both Assertion and Reason are incorrect

Answer 1

Fractional distillation is the process of separation of a mixture of substances into its fractions or constituents or components and it can be done by heating the mixture at a temperature where one or more fraction of mixture will vaporize.

Complete answer:
As discussed, fractional distillation is the process of separation of a mixture of substances into its fractions or constituents or components and it can be done by heating the mixture at a temperature where one or more fraction of mixture will vaporize. The components differ in their boiling point by less than ${25^ \circ }C$.
Let us talk about the fractional distillation chamber, it is a tall fractional distillation column which is fitted above the mixture along with several condensers at different heights. The column is hot at bottom and cool at the top. Remember that substances with high boiling points will condense at the bottom of the column and the one with the lower boiling point will condense on the top of the column.
Now, we know that petroleum is obtained from the crude oil as a fraction. Crude oil inside the distillation tank is heated, the liquids and vapours separate into petroleum components or fractions according to their boiling points. Liquefied gases and gasoline are the lightest fractions so they will vapour rise and rise at the top of the distillation column where they will be condensed back to liquids.
Kerosene and distillates like diesel, lubricating oil and heating oil which are of medium weight stays in the middle of the distillation column and the heavier liquids like gas oils and fuel oils with higher boiling points will settle at the bottom.
Therefore we can say that fractional distillation separates the heterogeneous mixtures and petroleum constituents can be separated by the same technique.

Hence, the correct answer is (A).

Note: Petroleum and its constituents can be used as fuels in transports, fuel oils for heating and generating electricity. Chemicals, plastic and synthetic materials are generally created using petroleum.