Thin-layer chromatography separates components of a mixture based on which property?

• A. Differences in electrical conductivity
• B. Differences in polarity
• C. Differences in molecular mass
• D. Differences in boiling point

Answer: (B)

Verified step by step guidance

1. Understand that thin-layer chromatography (TLC) is a technique used to separate components of a mixture based on how they interact with two phases: the stationary phase and the mobile phase.
2. Recognize that the stationary phase in TLC is usually a polar substance, such as silica gel or alumina, which interacts differently with compounds depending on their polarity.
3. Know that the mobile phase is a solvent or mixture of solvents that moves up the TLC plate by capillary action, carrying the components of the mixture along with it.
4. Realize that components with different polarities will have different affinities for the stationary phase versus the mobile phase, causing them to travel different distances on the TLC plate.
5. Conclude that the separation in TLC is primarily based on differences in polarity, where more polar compounds interact strongly with the polar stationary phase and move slower, while less polar compounds move faster with the mobile phase.