Organic Chemistry MCAT Practice Exam

What is formed when triacylglycerol undergoes saponification?

1. Fatty acids and glycerin

2. Glycerol and free fatty acids

3. Glycerol and fatty acid esters

4. Saturated fatty acids and alcohols

The correct answer is: Glycerol and free fatty acids

When triacylglycerol undergoes saponification, the reaction typically involves the hydrolysis of the ester bonds present in the triacylglycerol molecule, usually in the presence of a strong base such as sodium hydroxide (NaOH) or potassium hydroxide (KOH). During this process, the triacylglycerol is broken down into its component parts: glycerol and free fatty acids. The saponification reaction can be summarized as follows: 1. Each ester bond in the triacylglycerol is cleaved, resulting in the release of glycerol, which is a three-carbon alcohol. 2. Each fatty acid chain that was attached to glycerol will be released in its free form. In saponification, these fatty acids can be saturated or unsaturated, depending on the structure of the original triacylglycerol. Option B accurately describes the products of this reaction, specifically highlighting the formation of glycerol and free fatty acids. This understanding is key in organic chemistry, particularly in the context of lipids and their transformations, which are vital in various biological and chemical processes.