Question

The alkaline nature of amines is due to the:

• A. small size of nitrogen.
• B. higher stability of nitrogen molecule at room temperature.
• C. presence of unshared pair of electrons on nitrogen.
• D. pyramidal geometry of nitrogen in amines.

Hint:

Nitrogen's lone pair is the "hand" that reaches out to grab a proton.

Answer 1

The Correct Option is C

Step 1: Concept
According to the Lewis theory, a base is an electron-pair donor.

Step 2: Meaning
Amines consist of a nitrogen atom with three bonds and one lone pair of electrons.

Step 3: Analysis
The lone pair on the nitrogen atom can be donated to a proton ($H^+$) or a Lewis acid. This ability to donate an electron pair makes the molecule basic (alkaline).

Step 4: Conclusion
Therefore, the lone pair of electrons is the structural feature responsible for the basicity of amines. Final Answer: (C)