Azeotropes are defined as a mixture of two liquids which has a constant composition in liquid and vapour phase at all temperatures.
Each azeotrope has a characteristic boiling point.
The boiling point of an azeotrope is either less than the boiling point temperatures of any of its constituents (a positive azeotrope), or greater than the boiling point of any of its constituents (a negative azeotrope).
There are two types of Azeotropes
(i) Maximum Boiling Azeotrope: Maximum Boiling Azeotrope is formed when we mix two non-ideal solutions at some specific composition, showing large negative deviation from Raoult’s law.
(ii) Minimum Boiling Azeotrope: Minimum Boiling Azeotrope is formed when we mix two non-ideal solutions at some specific composition, which shows large positive deviation from Raoult’s Law.
Example: Ethanol ( 95.5%) and water (4.5%) form minimum boiling azeotrope at boiling temperature of 351.5 K
Types of azeotrope