Question

What is the name of second lower homologue of \(\text{CH}_3(\text{CH}_2)_2\text{COOH}\) ?

• A. Methanoic acid
• B. Ethanoic acid
• C. Propanoic acid
• D. Pentanoic acid

Hint:

Each lower homologue has one CH2 group fewer.

Answer 1

The Correct Option is B

Step 1: Count carbons:
$\text{CH}_3(\text{CH}_2)_2\text{COOH}$: 1 + 2 + 1 = 4 carbons.

Step 2: Step down by two:
4 - 2 = 2 carbons, so the acid is $\text{CH}_3\text{COOH}$, ethanoic acid (B).

Final Answer:
Ethanoic acid. \[ \boxed{\text{(B)}} \]