FreeMCATPrep Logo

More Than 475 Free MCAT Questions with Detailed Answers!

Click HERE for your Random Question from our MCAT Question A Day Archive

MCAT Question A Day - 4/10/13 - Answer!

In both dehydration and substitution reactions of alcohols,

A.  heating is required.
B.  only tertiary alcohols react.
C.  —OH is the leaving group.
D.  protonation usually occurs first because —OH is a poor leaving group.

The correct answer is (D). —OH is a poor leaving group. Protonation allows H2to leave so that dehydration and substitution can occur.