The most stable trihalide of nitrogen is : Question:

Options

A. `NF_3`
B. `NCl_3`
C. `NBr_3`
D. `NI_3`

Answer

To determine the most stable trihalide of nitrogen, we need to analyze the stability of the various nitrogen trihalides: NF3, NCl3, NBr3, and NI3.

### Step-by-Step Solution:

1. **Identify the Trihalides**: The nitrogen trihalides we need to consider are:
- NF3 (Nitrogen trifluoride)
- NCl3 (Nitrogen trichloride)
- NBr3 (Nitrogen tribromide)
- NI3 (Nitrogen triiodide)

2. **Consider the Electronegativity of Halogens**: The stability of these compounds is influenced by the electronegativity of the halogen atoms. The order of electronegativity for the halogens is:
- Fluorine (F) > Chlorine (Cl) > Bromine (Br) > Iodine (I)

3. **Analyze the Size of Halogens**: The size of the halogen atoms increases down the group:
- Fluorine is the smallest, followed by chlorine, bromine, and iodine.
- Larger atoms (like iodine) tend to form weaker bonds with nitrogen due to increased bond length and decreased overlap.

4. **Evaluate Bond Strength and Stability**:
- NF3 has strong N-F bonds due to the high electronegativity of fluorine, which leads to a stable compound.
- NCl3, NBr3, and NI3 have weaker N-X bonds (where X is Cl, Br, or I) because of the larger size and lower electronegativity of these halogens compared to fluorine.

5. **Conclusion**: Based on the analysis of electronegativity, bond strength, and size of the halogens, NF3 is the most stable nitrogen trihalide due to the strong N-F bonds and the high electronegativity of fluorine.

### Final Answer:
The most stable trihalide of nitrogen is **NF3**.

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