Eduprobe
Question:
Two compounds I and II are eluted by column chromatography (adsorption of I > II). Which one of the following is a correct statement?
II moves slower and has higher Rf value than I
I moves faster and has higher Rf value than II
II moves faster and has higher Rf value than I
I moves slower and has higher Rf value than II
Solution:
Two compounds I and II are eluted by column chromatography (adsorption of I > II). The statement (B) is a correct statement. Since compound I is more strongly adsorbed (adsorption of I > II), it will move slower than compound II. The Rf value is a measure of how far a compound travels relative to the solvent front. A higher Rf value indicates faster movement. Therefore, compound II, moving faster, will have a higher Rf value than compound I.