Question

A chromatography column, packed with silica gel as stationary phase, was used to separate a mixture of compounds consisting of (A) benzanilide, (B) aniline and (C) acetophenone. When the column is eluted with a mixture of solvents, hexane : ethyl acetate (20:80), the sequence of obtained compounds is:

• A. (B), (A) and (C)
• B. (C), (A) and (B)
• C. (B), (C) and (A)
• D. (A), (B) and (C)

Answer 1

The correct option is B (C), (A) and (B)

Since the column is eluted with the solvent having more proportion of ethyl acetate, the more polar compound will come out first.

The order of polarity in the given compounds is ;
acetophenone > benzanilide > aniline.

Dipole moment $\left(\mu \right)$ of
acetophenone=3.05 D,
benzanilide=2.71 D
and aniline=1.59 D.