Question

Which of the following liquid pairs shows negative deviation from Raoult’s law?

• A. Phenol - Aniline
• B. Acetone - Carbon disulphide
• C. Benzene - Toluene
• D. n-hexane — n-heptane
• E. Bromoethane — Chloroethane

Hint:

Negative deviations from Raoult’s law are observed when the components of a mixture have stronger intermolecular forces than in the pure substances.

Answer 1

The Correct Option is A

Negative deviation from Raoult’s law occurs when the intermolecular forces between the molecules of the liquid are stronger than those between the molecules of the individual components. In the case of phenol and aniline, hydrogen bonding leads to a stronger interaction between the two components, causing a negative deviation.