Question

Which of the following amines is not represented by formula \(\text{C}_3\text{H}_9\text{N}\) ?

• A. \(1^{\circ}\) amine
• B. \(2^{\circ}\) amine
• C. \(3^{\circ}\) amine
• D. quaternary ammonium salt

Hint:

C3H9N can be a primary, secondary or tertiary amine, but a quaternary ammonium salt has four carbon groups on N.

Answer 1

The Correct Option is D

Step 1: Enumerate isomers
Propylamine, isopropylamine (1), ethylmethylamine (2), trimethylamine (3).

Step 2: Quaternary
Four alkyl groups on N need at least 4 carbons and give a cation, not a neutral amine.

Step 3: Answer
Option (D).

Final Answer:
Option (D). \[ \boxed{\text{Quaternary ammonium salt}} \]