The least electronegative element has the following electronic configuration

Options

A. `ns^(2)np^(5)`
B. `ns^(2) np^(4)`
C. `ns^(2) np^(3)`
D. `ns^(2) np^(6)`

Answer

To determine the least electronegative element based on the given electronic configurations, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Electronegativity**:
- Electronegativity refers to the tendency of an atom to attract shared electrons in a chemical bond. Nonmetals generally have higher electronegativities than metals.

2. **Analyzing the Given Electronic Configurations**:
- The electronic configurations provided are:
1. ns²np⁵
2. ns²np⁴
3. ns²np³
4. ns²np⁶

3. **Identifying the Valence Electrons**:
- For each configuration:
- **ns²np⁵**: This configuration has 7 valence electrons (2 from ns and 5 from np). It requires 1 more electron to complete its octet, making it highly electronegative.
- **ns²np⁴**: This configuration has 6 valence electrons. It requires 2 more electrons to achieve an octet, indicating it is also electronegative.
- **ns²np³**: This configuration has 5 valence electrons. It requires 3 more electrons to complete its octet, making it less electronegative than the previous two.
- **ns²np⁶**: This configuration has 8 valence electrons, indicating a complete octet. Elements with this configuration are stable and do not attract electrons, resulting in zero electronegativity.

4. **Conclusion**:
- Among the configurations analyzed, the element with the configuration **ns²np⁶** is the least electronegative because it has a complete octet and is stable, thus exhibiting zero electronegativity.

### Final Answer:
The least electronegative element corresponds to the electronic configuration **ns²np⁶**.

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