Rf Value Calculator Formula
Understand the math behind the rf value calculator. Each variable explained with a worked example.
Formulas Used
Rf Value
rf = dist_solute / dist_solventVariables
| Variable | Description | Default |
|---|---|---|
dist_solute | Distance Traveled by Solute(cm) | 3.5 |
dist_solvent | Distance Traveled by Solvent Front(cm) | 7 |
How It Works
Retention Factor (Rf) in TLC
The Rf value describes how far a compound moves relative to the solvent front in thin-layer chromatography. It is characteristic of a compound under specific conditions.
Formula
Rf = distance traveled by solute / distance traveled by solvent front
Rf values range from 0 (compound stays at origin) to 1 (compound moves with solvent front). Polar compounds have lower Rf values on silica plates because they interact more strongly with the polar stationary phase.
Worked Example
A spot on a TLC plate travels 3.5 cm while the solvent front reaches 7.0 cm.
dist_solute = 3.5dist_solvent = 7
- 01Rf = 3.5 / 7.0 = 0.500
Ready to run the numbers?
Open Rf Value Calculator