Question 1

What is the basic principle of distillation?

Accepted Answer

Distillation separates a liquid mixture using differences in the boiling points or volatilities of its components. The more volatile component forms vapour more readily and is led into a condenser, while the less volatile component remains in the distillation flask for longer.

Question 2

Why does cooling water enter the lower port of a condenser?

Accepted Answer

Water enters from the lower port and leaves through the upper port so the jacket remains full and can cool the vapour passing through the inner tube. The condenser slopes downward toward the receiver; this slope, not the coolant flow, makes the condensate drain into the receiver.

Question 3

Does simple distillation always produce a pure liquid at one temperature?

Accepted Answer

No. A simple distillation of a mixture may produce distillate over a range of boiling temperatures. The composition of the collected distillate can change as the more volatile component is gradually removed.

Question 4

How does a fractionating column improve separation?

Accepted Answer

A fractionating column provides repeated condensation-vaporisation cycles. Bead-packed columns and Vigreux columns are alternative designs, and their internals help the less volatile component remain lower while more volatile vapour travels towards the condenser.

Question 5

What is the purpose of steam distillation?

Accepted Answer

Steam distillation is used for a liquid that is immiscible with water. Live steam carries the volatile material along with water vapour, allowing the combined vapours to be condensed and collected as a separate layer.

Distillation Bench — Simple, Fractional & Steam in One Glass Rig

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