NEETChemistrySolutions
When phenol and aniline are mixed, they form a non-ideal solution. Which of the following correctly describes the thermodynamic properties of mixing and the type of azeotrope formed by this solution?
Options
- A_ mix H > 0 , _ mix V > 0 , forms a minimum boiling azeotrope
- B_ mix H < 0 , _ mix V < 0 , forms a minimum boiling azeotrope
- C_ mix H < 0 , _ mix V < 0 , forms a maximum boiling azeotrope
- D_ mix H = 0 , _ mix V = 0 , does not form an azeotrope
Correct answer
C. _ mix H < 0 , _ mix V < 0 , forms a maximum boiling azeotrope
Step-by-step solution
A mixture of phenol and aniline shows a negative deviation from Raoult's law. This occurs because the intermolecular hydrogen bonding between the phenolic proton and the lone pair on the nitrogen atom of aniline is stronger than the intermolecular forces in the pure liquids. For solutions showing a negative deviation, the stronger attractive forces result in the release of heat ( _ mix H Furthermore, solutions that show a large negative deviation from Raoult's law form maximum boiling azeotropes at a specific compo