Question

A triglyceride can be optically active if it contains two or more different fatty acids

1. Draw the structure of an optically active triglyceride containing one equivalent of myristic acid and two equivalents of oleic acid.
2. Draw the structure of an optically inactive triglyceride with the same fatty acid composition.

Short answer

A triglyceride is an ester derived from glycerol and three fatty acids. It is optically active or inactive depending on structures.

Step-by-step solution

Step 1:

A triglyceride is an ester derived from glycerol and three fatty acids. It is optically active or inactive depending on structures.

Step 2:

The molecular formula of myristic acid and oleic acid are C₁₄H₂₈O₂ and C₁₈H₃₄O₂. For an optically active triglyceride, fatty acids are arranged in such a manner that there is no symmetry present in whole structure. In the below structure there is no symmetry element present in triglyceride. Hence is optically active.

Step 3:

For an optically inactive triglyceride, fatty acids are arranged in such a manner that there is symmetry present in whole structure. In the below structure there is the plane of symmetry present in triglyceride. Hence is optically inactive.