In chromatography, substances (solutes) are separated (from a mixture) based on how fast they move in a mobile phase and their relative partitioning between the mobile and stationary phase. Acetone is commonly used as a solvent in chromatography. It is an amphipathic molecule, i.e. it has both polar and non-polar ends. It is a better solvent than water, since it can dissolve both polar and non-polar solutes and is capable of separating them easily. However, it cannot be used at 100% concentration. When used at that concentration, it travels too fast through the column and does not result in separation of individual solutes. A concentration of 50% acetone was found to be more effective. Check the attached link for detailed experimental information on the efficiency of various concentrations of acetone.
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