Question

What is the combining ratio of glycerol and fatty acids when they combine to form triglyceride?

• A. 3 : 4
• B. 3 : 2
• C. 1 : 3
• D. 1 : 2

Answer 1

The correct option is C 1 : 3

Glycerol is an alcohol with three carbons, five hydrogens, and three hydroxyl (OH) groups.

Fatty acids have a long chain of hydrocarbons with a carboxyl group attached and may have $4-36$ carbons.

In a fat molecule, the fatty acids are attached to each of the three carbons of the glycerol molecule with an ester bond through the oxygen atom. During the ester bond formation, three molecules are released. Since fats consist of three fatty acids and a glycerol, they are also called triacylglycerols or triglycerides.

For 1 molecule of glycerol, we need 3 molecules of fatty acids so, $1:3$.