The two compounds whose structures are depicted here are isomers. When derived from petroleum, they always occur mixed together. meta-Xylene is used in aviation fuels and in the manufacture of dyes and insecticides. The principal use of paraxylene is in the manufacture of polyester resins and fibers (for example, Dacron). Comment on the effectiveness of fractional distillation as a method of separating these two xylenes. What other method(s) might be used to separate them?

CH3 CH3 meta-xylene fp, 47.9 C bp, 139.1 C d, 0.864 g/mL CH3 CH3 para-xylene fp, 13.3 C bp, 138.4 C d, 0.861 g/mL