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thin layer chromatography A mixture of compounds A and B was run on TLC using 10

ID: 891168 • Letter: T

Question

thin layer chromatography A mixture of compounds A and B was run on TLC using 10% ethyl acetate/90% hexanes, and the Rf values of 0.05 and 0.12 were obtained. Is this optimal? How can the separation be improved? Assume that compounds A and B have Rf values of 0.3 and 0.5, respectively. How far will each of these compounds travel if the solvent front reaches 8 cm? A mixture of p-methylstyrene, p-methostyrene, and p-cresol (p-methylphenol) is run on a TLC plate. Match the three compounds to the following Rf values: 0.15,0.42, 0.65.

Explanation / Answer

3-0.65-p-methylstyrene

0.42- p-cresol

0.15 - p- methostyrene

2- Rf= distance traveled by the compound / distance traveled by the solvent

0.3=distance traveled by the compound /8cm

distance traveled by the compound =2.4cm

0.5=distance traveled by the compound /8cm

distance traveled by the compound =4cm

1- yes, If the speration between the spots are very close then run the TLC plate repeatedly with eluents with gradual increase polarity.