Which would be better in TLC?

Question

The Rf value of compound A is 0.34 when developed in hexane and 0.47 when developed in dichloromethane. Compound B has Rf Value of 0.42 in hexane and 0.69 in dichloromethane. Which solvent will be better for separating a mixture of compound A and B?

Answer 1

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Answer 2

I would use DCM.  You are getting better separation between the 2 compounds with that solvent (difference of 0.08 with hexane compared with difference of 0.22).  If you let the solvent front run 5cm, then using DCM the compounds would have 11mm separating them, whilst using hexane the distance between them would only be 4mm (Rf value is the ratio of distance samples moved to the distance the sovloent fronts moved)