Question

Number of steps required for the separation of two liquids in fractional distillation is _________

(a) 1

(b) 2

(c) 3

(d) 4

This question was addressed to me in exam.

This is a very interesting question from Fractional Distillation in section Methods of Purification of Engineering Chemistry I

Answer 1

The correct answer is (b) 2

For explanation: Number of steps required for the separation of two liquids in fractional distillation is 2. Vacuum distillation systems operate at reduced pressure, thereby lowering the boiling points of the materials. Anti-bumping granules, however, become ineffective at reduced pressures.