Question

What is the number of $>\text{C} = \text{C}<$ bonds present in a linolenic acid molecule?

• A. Zero
• B. One
• C. Two
• D. Three

Hint:

Remember the order 1, 2, 3 for Oleic, Linoleic, and Linolenic acids respectively.

Answer 1

The Correct Option is D

Linolenic acid is a type of polyunsaturated fatty acid essential for human health. Its molecular formula is \(C_{18}H_{30}O_2\), and it's known for containing multiple double bonds in its carbon chain.

To answer this question, we need to examine the structure of linolenic acid to identify the number of carbon-carbon double bonds present. Linolenic acid, particularly alpha-linolenic acid (ALA), is structured as an 18-carbon chain with three double bonds.

1. Firstly, the structure of the most common form of linolenic acid, alpha-linolenic acid, is typically written as 18:3(Δ9,12,15). This notation means that there are 18 carbon atoms in the chain, and there are double bonds at the 9th, 12th, and 15th carbon atoms.
2. The presence of these double bonds is what signifies the \(\text{C} = \text{C}\) bonds in the fatty acid. Each location in the specification (Δ9,12,15) indicates a C=C double bond.
3. Counting these, there are exactly three carbon-carbon double bonds in alpha-linolenic acid.

Thus, the number of \(\text{C} = \text{C}\) bonds present in a linolenic acid molecule is three.