Question

Which of the following is most basic?

• A. \(CH_3CH_2NH_2\)
• B. \(CH_3CONH_2\)
• C. \(C_6H_5CONH_2\)
• D. \(NH_2NH_2\)

Hint:

Order of basicity: Aliphatic amines>Ammonia>Aromatic amines>Amides.

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
Basicity depends on the availability of the lone pair on nitrogen. Electron-donating groups increase basicity, while electron-withdrawing groups decrease basicity.
Step 2: Detailed Explanation:
\begin{itemize} \item (A) \(CH_3CH_2NH_2\) (ethylamine): Aliphatic amine with electron-donating ethyl group, strong base. \item (B) \(CH_3CONH_2\) (acetamide): The carbonyl group is electron-withdrawing, delocalizing the lone pair on nitrogen through resonance, reducing basicity. \item (C) \(C_6H_5CONH_2\) (benzamide): Similar to acetamide, but the phenyl ring further reduces basicity due to conjugation. \item (D) \(NH_2NH_2\) (hydrazine): Less basic than ethylamine due to the electron-withdrawing effect of the additional \(NH_2\) group. \end{itemize}
Step 3: Final Answer:
Ethylamine is the most basic, option (A).