What does a smaller Rf value indicate?

What does a smaller Rf value indicate?

• A. The compound traveled less and interacted more strongly with the stationary phase
• B. The compound traveled farther and interacted less with the stationary phase
• C. The compound traveled less and interacted less with the stationary phase
• D. The compound traveled more and interacted more with the stationary phase

Answer: (A)

In TLC, the Rf value reflects how far a compound travels relative to the solvent front. A small Rf means the compound moved only a short distance, which happens when it interacts more strongly with the stationary phase (the solid, like silica) than with the mobile phase (the solvent). This stronger attraction to the stationary phase keeps the substance near the origin, so its traveled distance is small and its Rf is small. In short, a smaller Rf indicates the compound traveled less and interacted more with the stationary phase (often due to greater polarity or stronger adsorption to the stationary phase).

In TLC, the Rf value reflects how far a compound travels relative to the solvent front. A small Rf means the compound moved only a short distance, which happens when it interacts more strongly with the stationary phase (the solid, like silica) than with the mobile phase (the solvent). This stronger attraction to the stationary phase keeps the substance near the origin, so its traveled distance is small and its Rf is small. In short, a smaller Rf indicates the compound traveled less and interacted more with the stationary phase (often due to greater polarity or stronger adsorption to the stationary phase).