Ammonia has abnormally high boiling point because it has

Options

A. Alkaline nature
B. Distored shape
C. `sp^(3)` hybridisation
D. Hydrogen bonding.

Explanation

To understand why ammonia (NH₃) has an abnormally high boiling point, we can analyze the molecular structure and the types of intermolecular forces present. Here’s a step-by-step breakdown of the solution:

### Step 1: Identify the Molecular Structure of Ammonia
Ammonia consists of one nitrogen atom bonded to three hydrogen atoms. The molecular formula is NH₃. The nitrogen atom has a lone pair of electrons.

### Step 2: Understand Electronegativity
Nitrogen is more electronegative than hydrogen. This means that the nitrogen atom attracts the shared electrons in the N-H bonds more strongly than the hydrogen atoms do. This creates a polar molecule, with a partial negative charge on the nitrogen and a partial positive charge on the hydrogens.

### Step 3: Recognize the Presence of Hydrogen Bonding
Due to the polarity of the NH bonds, ammonia molecules can form hydrogen bonds. A hydrogen bond is a strong type of dipole-dipole attraction that occurs between a hydrogen atom bonded to a highly electronegative atom (like nitrogen) and another electronegative atom.

### Step 4: Compare with Other Molecules
When comparing ammonia to other similar molecules, such as methane (CH₄), which does not have hydrogen bonding, we can see that the boiling point of ammonia is significantly higher. This is because the hydrogen bonds in ammonia require more energy to break compared to the weaker van der Waals forces present in methane.

### Step 5: Conclusion
The abnormally high boiling point of ammonia can be attributed to the presence of hydrogen bonding between ammonia molecules. This strong intermolecular force leads to a higher boiling point than would be expected for a molecule of its size.

### Final Answer
Ammonia has an abnormally high boiling point because it has hydrogen bonding.

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