Question

Choose the correct statement from the options given

• A. The decreasing order of basic nature of the following amines is: Methylamine \( > \) Dimethylamine \( > \) Trimethylamine \( > \) Aniline.
• B. The intermolecular bonding in primary amines is stronger than in secondary amines.
• C. Benzene diazonium chloride when reacted with Aniline in presence of dil. HCl at 273 K yields \( C_6H_5 - N = N - NH - C_6H_5 \).
• D. On heating an aliphatic primary amine with \( CHCl_3 \) in presence of Ethanolic KOH, a Nitrile is formed.

Hint:

Primary amines show stronger hydrogen bonding due to more N-H bonds, and carbylamine reaction gives isocyanides, not nitriles.

Answer 1

The Correct Option is B

Step 1: Analyze option (A).
In aqueous solution, the correct order of basic strength is generally:
\[ \text{Dimethylamine} > \text{Methylamine} > \text{Trimethylamine} > \text{Aniline} \]
Thus, the given order is incorrect.

Step 2: Analyze option (B).
Primary amines have two hydrogen atoms attached to nitrogen, allowing more extensive hydrogen bonding between molecules.
Secondary amines have only one hydrogen atom, so intermolecular hydrogen bonding is comparatively weaker.
Thus, this statement is correct.

Step 3: Analyze option (C).
Benzene diazonium chloride reacts with aniline in mildly alkaline medium (not acidic) to form azo compounds.
Also, the product structure given is incorrect.
Thus, this statement is incorrect.

Step 4: Analyze option (D).
Aliphatic primary amines with \( CHCl_3 \) and ethanolic KOH give isocyanides (carbylamine reaction), not nitriles.
Thus, this statement is incorrect.

Step 5: Conclusion.
Only option (B) is correct.
Therefore:
\[ \boxed{\text{The intermolecular bonding in primary amines is stronger than in secondary amines}} \]