The largest oxidation number exhibited by an element depends on its outer eletronic configuration. With which of the following outer electronic configurations the element will exhibit largest oxidation number ?

Options

A. `3d^(1)4s^(2)`
B. `3d^(3)4s^(2)`
C. `3d^(5)4s^(1)`
D. `3d^(5)4s^(2)`

Explanation

To determine which outer electronic configuration corresponds to the largest oxidation number, we need to analyze the given configurations and understand how the oxidation number is related to the number of valence electrons that can be lost or shared during a chemical reaction.

### Step-by-Step Solution:

1. **Understand Oxidation Numbers**: The oxidation number of an element indicates the degree of oxidation (loss of electrons) of that element in a compound. The maximum oxidation number is typically equal to the number of valence electrons that can be lost.

2. **Identify the Outer Electronic Configurations**: The question provides several outer electronic configurations. Let's denote them as follows:
- A: ns²
- B: ns²np³
- C: ns²np⁶
- D: ns²np⁵

3. **Evaluate Each Configuration**:
- **Configuration A (ns²)**: This configuration has 2 valence electrons. The maximum oxidation number is +2.
- **Configuration B (ns²np³)**: This configuration has 5 valence electrons (2 from s and 3 from p). The maximum oxidation number is +5.
- **Configuration C (ns²np⁶)**: This configuration has 8 valence electrons, which corresponds to a noble gas configuration. The maximum oxidation number is usually 0, as noble gases do not typically form compounds.
- **Configuration D (ns²np⁵)**: This configuration has 7 valence electrons (2 from s and 5 from p). The maximum oxidation number is +7.

4. **Determine the Largest Oxidation Number**: From the evaluations:
- A: +2
- B: +5
- C: 0
- D: +7

The largest oxidation number among these configurations is +7, which corresponds to configuration D (ns²np⁵).

5. **Conclusion**: Therefore, the outer electronic configuration that allows for the largest oxidation number is **D (ns²np⁵)**.

### Final Answer:
The element with the outer electronic configuration ns²np⁵ will exhibit the largest oxidation number of +7.