Question

Which method is applied for purification of liquid which decompose before their boiling point?

Answer 1

Vacuum distillation is used to purify a liquid which decomposes at or below its boiling point.In this method, the pressure over liquid is reduced by using a vacuum pump due to which the liquid boils at a temperature below its boiling point and thus decomposition of liquid is prevented.Example:Glycerol which decomposes at 563 K boils at 453 K at a pressure of 12mm.