Question

Which of the following solvent pairs could be used in a solvent pair recrystallization (in general, not for this specific reaction)? For those selected, briefly explain why. For those not selected, briefly explain why not.

(a) Ethyl acetate and hexane
(b) Water and diethyl ether
(c) Methanol and methylene chloride

Answer 1

(a) Ethyl acetate and hexane, and (c) methanol and methylene chloride.

Step-by-step explanation:

re-crystallization is a technique used to purify solid compound. Ethyl acetate and hexane are good solvent pair for recrystallization because they are miscible with each other due to their good differences in polarity. ethyl acetate has polarity of 77 while hexane has 68.

water and diethyl ether are not good solvent pair for recrystallization because water and diethyl ether are immiscible. They have very far polarity values. water has 100 while diethyl ether has 35