Chemistry – Experimental techniques and chemical analysis - Chromatography | e-Consult

The Rf value (retardation factor) is a measure of the distance travelled by a substance in chromatography relative to the distance travelled by the solvent. It is calculated as: Rf = (distance travelled by the substance) / (distance travelled by the solvent from the origin). The Rf value ranges from 0 to 1.

A higher Rf value indicates that the substance is more soluble in the mobile phase (solvent) and therefore travels further up the paper. A lower Rf value indicates that the substance is less soluble in the mobile phase and travels less far.

Dye C has the highest Rf value (0.8), meaning it travelled the furthest. Therefore, Dye C is the most likely to be non-polar. Non-polar substances are more soluble in non-polar solvents. Since Dye C travelled the furthest, it must have a stronger affinity for the non-polar component of the solvent (or the stationary phase if the paper is also relatively non-polar). Dyes A and B have lower Rf values, indicating they are more polar and therefore less soluble in the solvent.