A mixture of three compounds $A, B, C$ is passed through a column of $\mathrm{Al}_2 \mathrm{O}_3$ by using…
A mixture of three compounds $A, B, C$ is passed through a column of $\mathrm{Al}_2 \mathrm{O}_3$ by using alcohol as eluant. The order in which they are eluted out of the column is $C, B, A$. Which of the following statement is true?
' $C$ ' is strongly adsorbed on the adsorbent
' $C$ ' is weakly adsorbed on the adsorbent
' $A$ ' is weakly adsorbed on the solvent
The order or elution does not depend on the extent of adsorption
Solution
Since, compound $C$ comes out before $B . B$ is more readily adsorbed to the column and ' $B$ ' comes out before $A$. Hence, $A$ is more readily adsorbed than $B$. Hence, order of adsorption is $A>B>C$. Hence, $C$ is weakly adsorbed on the adsorbent. Thus, the correct option is (b).