Question

25-2Why does the retention onder of peaks 2 and 3 change on the polar embedded column?

Short answer

Compound 2 has polar functionalities that could interact with the polar embedded groups, increasing retention. Compound 3 cannot interact with these groups

Step-by-step solution

Define interpretation

Interpretation:

The reason why the retention order of compound 2 and compound 3 changes on polar embedded column has to be explained..

Concept Introduction:

Retention of the compound depends upon the functional groups that are present in it and the column that is used for HPLC. If a polar column is used means the polar compounds gets attracted more and vice-versa.

Explanation

Compound 2 is 4-butylbenzoic acid and compound 3 is toluene. By looking into the two compounds, we find that compound 2 has a polar acid group, while compound 3 does not have polar groups. Therefore, when using polar embedded column for HPLC, compound 2 interacts more than compound 3 due to the presence of the polar acidic group. Compound 3 does not have any polar groups and this does not interact with the polar embedded column. Hence, the compound 2 has more retention compared to compound 3 . This is the reason why the retention order is changed in the polar embedded column.