Chemistry · Unit 2 · Intermolecular forces and gases · Intermolecular forces
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A student performs thin layer chromatography (TLC) on a silica gel plate using a non-polar solvent to separate three compounds in a mixture. After development, the following retention factors are measured: Compound X has an Rf of 0.20, Compound Y has an Rf of 0.55, and Compound Z has an Rf of 0.85. Which statement correctly describes the relative polarities of these compounds?
A student performs thin layer chromatography (TLC) to separate a mixture of three unknown dyes. The diagram shows the TLC plate after development and placement under ultraviolet (UV) light. The solvent front travelled 12.0 cm from the baseline. Which statement correctly describes the relative polarity of the three separated dyes based on their positions on the plate?
In a thin layer chromatography (TLC) experiment, a mixture of three amino acids is separated on a silica gel plate using an organic solvent as the mobile phase. The retention factor (\(R_f\)) for each amino acid is calculated as \(R_f = \frac{\text{distance moved by amino acid}}{\text{distance moved by solvent front}}\). Which statement correctly describes what happens to an amino acid with a high \(R_f\) value during this separation?