Question

Assertion (A): Boiling point of (CH₃)₃N is higher than that of CH₃CH₂CH₂NH₂.
Reason (R): Hydrogen bonding is more extensive in CH₃CH₂CH₂NH₂.

• A. Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A).
• B. Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of the Assertion (A).
• C. Assertion (A) is true, but Reason (R) is false.
• D. Assertion (A) is false, but Reason (R) is true.

Hint:

When comparing boiling points, remember that hydrogen bonding plays a significant role in raising the boiling point of amines.

Answer 1

The Correct Option is B

(CH₃)₃N (trimethylamine) exhibits a lower boiling point than CH₃CH₂CH₂NH₂ (propylamine) because propylamine engages in hydrogen bonding, a phenomenon absent in trimethylamine. Thus, the lower boiling point of (CH₃)₃N is attributable to its deficiency in hydrogen bonding, rather than an abundance of it in CH₃CH₂CH₂NH₂. Consequently, Assertion (A) is valid, but Reason (R) does not accurately explain the phenomenon.