Chromatography Post lab Questions 1. After a rather lengthy organic chemistry synthesis procedure, a student ran the product of the reaction on a TLC plate and obtained the results below. What might the student have done wrong if anything? 2. What would happen to your column if you let the solvent drop below the top layer of sand? Explain. 3. If you are trying to separate a mixture of three compounds and all of the spots on a TLC plate are near the solvent front, would this be a good solvent to use for separation? What could you do to the mobile that would allow for a better separation? 4. Consider a sample that is a mixture composed of naphthalene, ethyl benzoate, and benzoic acid. The sample is spotted on a TLC plate and developed in a hexanes/ethyl acetate solvent mixture. Predict the relative Rf values for the three compounds in the sample.
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