Hi! The chlorphylls having lower Rf values indicates that they interact more strongly with the solvent. Both chlorophylls are polar while carotenes are non-polar. If the solvent being used for TLC is mostly non-polar, we would expect the carotenes to interact more strongly and have lower Rf values and vice versa. Other variations in Rf values (such as those between chlorophyll a and b) may indicate slight differences in polarity (perhaps there are nonpolar regions on the molecule even though it is polar overall) or differences in molecular weight (the heavier, the slower the molecule moves up the plate.) I hope this helps! Please don\'t forget to rate : ) Solution Hi! The chlorphylls having lower Rf values indicates that they interact more strongly with the solvent. Both chlorophylls are polar while carotenes are non-polar. If the solvent being used for TLC is mostly non-polar, we would expect the carotenes to interact more strongly and have lower Rf values and vice versa. Other variations in Rf values (such as those between chlorophyll a and b) may indicate slight differences in polarity (perhaps there are nonpolar regions on the molecule even though it is polar overall) or differences in molecular weight (the heavier, the slower the molecule moves up the plate.) I hope this helps! Please don\'t forget to rate : ).