Question

Which of the following statements is/are correct w.r.t. the solution obtained by mixing phenol and aniline?

• A. It shows a positive deviation as the $H-$ bond in aniline is stronger than the $H-$ bond between phenol and aniline
• B. It shows a negative deviation as the $H-$ bond between the phenolic proton and lone pair on $N$ atom is stronger than the respective intermolecular $H-$ bond between similar molecules.
• C. It shows a negative deviation as the $H-$ bond between lone pair of oxygen in phenol and the proton on$N$ in aniline is weaker than the respective intermolecular $H-$ bond between similar molecules.
• D. It shows a positive deviation as the $H-$ bond in phenol is stronger than the $H-$ bond between phenol and aniline

Answer 1

The correct option is B It shows a negative deviation as the $H-$ bond between the phenolic proton and lone pair on $N$ atom is stronger than the respective intermolecular $H-$ bond between similar molecules.

Greater the ${\delta }^{+}$ on $H$ and stronger the donation tendency of lone pair, stronger is the $H$ bond.
Phenolic proton and lone pairs of $N$ in aniline form strong $H$ bond which leads to a negative deviation from Raoult's law.