Which of the following is strong Lewis base?

Options

A. `NF_(3)`
B. `NCI_(3)`
C. `NBr_(3)`
D. `NI_(3)`

Answer

To determine which of the following is a strong Lewis base, we need to understand the concept of Lewis bases. A Lewis base is defined as a substance that can donate a lone pair of electrons to form a covalent bond.

### Step-by-Step Solution:

1. **Identify the Compounds**: First, we need to identify the compounds provided in the question. Let's assume the options include NF3, Ni3, and perhaps other compounds.

2. **Analyze Electronegativity**:
- **NF3**: In NF3, nitrogen is bonded to three fluorine atoms. Fluorine is highly electronegative, which means it pulls the bonding electrons towards itself. This results in a decrease in the availability of the lone pair of electrons on nitrogen, making NF3 a weak Lewis base.
- **Ni3**: In Ni3, nitrogen is bonded to three iodine atoms. Iodine is less electronegative than nitrogen. Therefore, the bonding electrons are pulled towards nitrogen, increasing the electron density on nitrogen. This makes the lone pair on nitrogen more available to donate, thus Ni3 is a stronger Lewis base.

3. **Compare the Lewis Basicity**:
- Between NF3 and Ni3, we can conclude that Ni3 has a higher electron density on nitrogen due to the lower electronegativity of iodine compared to fluorine. Hence, Ni3 is a stronger Lewis base than NF3.

4. **Final Conclusion**: Based on the analysis, Ni3 is the strongest Lewis base among the options provided.

### Final Answer:
Ni3 is the strongest Lewis base.

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