Question

You have a column chromatography with a lipid and protein and use silica beads (polar) as the stationary phase and hexane as the mobile phase. Which will elute out first?

A) Lipid
B) Protein
C) Both simultaneously
D) Neither

Answer 1

In a column chromatography setup using polar silica beads as the stationary phase and non-polar hexane as the mobile phase, the non-polar lipids will elute before the polar or charged proteins, making the lipid the substance to elute first.

Step-by-step explanation:

In column chromatography using silica beads as the stationary phase and hexane as the mobile phase, the substance that will elute out first is the one that interacts least with the stationary phase. Since silica is polar and the hexane is non-polar, lipids, which are generally non-polar, will have a lower affinity for the silica beads and higher solubility in hexane, causing them to elute first. Proteins, which are typically larger and may have polar or charged groups, will likely interact more with the polar silica beads and elute later. Therefore, the correct answer is A) Lipid.