Organic Chemistry MCAT Practice Exam 2025 – The All-in-One Guide to Master Your Test Preparation!

The acid-catalyzed dehydration of an alcohol typically leads to the formation of an alkene. This reaction involves the removal of a water molecule from the alcohol, facilitated by an acid catalyst, which protonates the alcohol to make the hydroxyl group a better leaving group.

In the presence of heat, the protonated alcohol undergoes elimination of water to form a carbocation intermediate. Depending on the stability of the carbocation, this intermediate can then lose a proton (H+) from an adjacent carbon, resulting in the formation of a double bond and yielding an alkene.

This process is a common method for synthesizing alkenes from alcohols and is often used in organic synthesis. It is also essential to understand that different factors, such as the structure of the alcohol and the reaction conditions, can influence the efficiency and selectivity of the alkene produced.

The other outcomes listed in the question do not occur in this specific acid-catalyzed dehydration reaction: alcohols are starting materials rather than products; ethers require a different mechanism; and aldehydes are typically formed from the oxidation of alcohols, not through dehydration.