The bond angles in `NH_(3), NF_(3) and NCl_(3)` are in the order:

Options

A. `NCl_(3) gt NH_(3) gt NF_(3)`
B. `NH_(3)gt NCl_(3) gt NF_(3)`
C. `NH_(3)gt NH_(3)gt NCl_(3)`
D. `NF_(3) gt NCl_(3) gt NH_(3)`

Answer

To determine the bond angles in NH₃, NF₃, and NCl₃, we will analyze the molecular geometry and the effects of lone pairs and electronegativity using VSEPR (Valence Shell Electron Pair Repulsion) theory.

### Step 1: Analyze NH₃ (Ammonia)
- **Structure**: NH₃ has a nitrogen atom bonded to three hydrogen atoms and has one lone pair of electrons.
- **Hybridization**: The nitrogen atom is sp³ hybridized.
- **Bond Angle**: The ideal bond angle for sp³ hybridization is 109.5°. However, the presence of the lone pair slightly reduces the bond angle due to lone pair-bond pair repulsion. The bond angle in NH₃ is approximately 107°.

### Step 2: Analyze NF₃ (Nitrogen Trifluoride)
- **Structure**: NF₃ has a nitrogen atom bonded to three fluorine atoms and also has one lone pair of electrons.
- **Hybridization**: The nitrogen atom is sp³ hybridized.
- **Electronegativity Effect**: Fluorine is highly electronegative, which pulls the bonding electrons closer to itself. This increases the bond pair-bond pair repulsion, resulting in a bond angle that is slightly less than the ideal 109.5°. The bond angle in NF₃ is approximately 102°.

### Step 3: Analyze NCl₃ (Nitrogen Trichloride)
- **Structure**: NCl₃ has a nitrogen atom bonded to three chlorine atoms and has one lone pair of electrons.
- **Hybridization**: The nitrogen atom is sp³ hybridized.
- **Bond Angle**: Chlorine is less electronegative than fluorine, which means the bond pair-bond pair repulsion is less pronounced compared to NF₃. Therefore, the bond angle in NCl₃ is larger than that in NF₃, approximately 107°.

### Conclusion: Order of Bond Angles
Based on the analysis:
- NCl₃ has the largest bond angle due to lower electronegativity and less repulsion.
- NH₃ has a bond angle that is slightly reduced due to lone pair repulsion.
- NF₃ has the smallest bond angle due to high electronegativity of fluorine.

Thus, the order of bond angles is:
**NCl₃ > NH₃ > NF₃**

### Final Answer
The bond angles in NH₃, NF₃, and NCl₃ are in the order: **NCl₃ > NH₃ > NF₃**.

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