What is Rf?
In paper chromatography, RF stands for retention factor, or the distance a liquid compound travels up a chromatography plate. The chromatography paper is the stationary phase and the liquid compound is the mobile phase; the liquid carries the sample solutions along the paper. When a liquid travels up the paper, it separates, allowing the person studying it to decipher the different components of the liquid solution. All compounds have a specific RF value for every specific solvent, and RF values are used to compare unknown samples with known compounds. Calculating RF is relatively simple with the right materials.
ref:Chemistry: Chromatography: RF Values and Paper Chromatography
Which pigment has the lowest Rf value?