Question

Which of the following best defines fractional distillation :

• A. Fractional distillation method is used if difference in boiling points of two liquids is very high
• B. Fractional distillation method is used if difference in boiling points of two liquids is not much and uses a fractionating column
• C. Purifying a sample that is contaminated with minerals
• D. None of these

Answer 1

The correct option is B Fractional distillation method is used if difference in boiling points of two liquids is not much and uses a fractionating column

Fractional distillation method is used if difference in boiling points of two liquids is not much and simple distillation can't be used to separate them.
In fractional distillation,vapours of liquid mixture are passed through a fractionating column before condensation.
Vapours rising up in the column become richer in more volatile (lower boiling point) component, as less volatile component loses heat and gets condensed.
Hence, the correct answer is option (b).