Based on our experiments which solvent mixture was best for

Based on our experiments, which solvent mixture was best for separating ibuprofen and naproxen?

Select one:

a. The acetic acid and 1,2-dichloroethane mixture.

b. The ethyl acetate and acetic acid mixture.

c. The 1,2-dichloroethane, acetone, ethanol, and hexanes mixture.

Solution

(B)

It is possible to use several developing solvents (eluents) for this experiment but ethyl acetate containing 0.5% glacial acetic acid is preferred. The small amount of acid supplies protons and suppresses ionization of aspirin and ibuprofen, allowing them to travel upward on the plates in their protonated form. Without the acid these compounds do not move.