5. (1.5 pts) The Rf value of compound A is 0.29 when developed in heptane and 0.47 when developed in chloroform. Compound B has an Rf value of 0.45 in heptane and 0.69 in chloroform. Which solvent would be better for separating a mixture of compounds A and B. Briefly explain your choice. 6. (1.5 pts) Why is it necessary to run TLC in a closed container and to have the interior vapor saturated with the solvent? = lowest 7. (1 pt) Rank in order of increasing eluting power for normal phase column chromatography (1 eluting power; 5 = greatest eluting power). 1:2 ethanol/CHCl3 hexane 1:1 ethanol/CHCl3 ethanol CHCl3