Which of the following electronic configuration is associated with the highest stable oxidation state?

Options

A. `[Ar]3d^(1)4s^(2)`
B. `[Ar]3d^(5)4s^(1)`
C. `[Ar]3d^(5)4s^(2)`
D. `[Ar]3d^(6)4s^(2)`

Answer

To determine which electronic configuration is associated with the highest stable oxidation state, we need to analyze the given electronic configurations and identify the one that is either half-filled or completely filled. The stability of oxidation states in transition metals is often linked to the electron configurations of their d and s orbitals.

### Step-by-Step Solution:

1. **Identify the Electronic Configurations**:
Let's denote the configurations as follows:
- A: 3d¹ 4s²
- B: 3d⁵ 4s²
- C: 3d⁴ 4s²
- D: 3d³ 4s²

2. **Determine Half-Filled and Fully Filled States**:
- A: 3d¹ (not half-filled, not fully filled), 4s² (fully filled)
- B: 3d⁵ (half-filled), 4s² (fully filled)
- C: 3d⁴ (not half-filled, not fully filled), 4s² (fully filled)
- D: 3d³ (not half-filled, not fully filled), 4s² (fully filled)

3. **Assess Stability Based on Electron Configuration**:
- The most stable configurations are those that are either half-filled or fully filled.
- The half-filled state (3d⁵) in configuration B is particularly stable because it provides maximum exchange energy and symmetry.

4. **Identify the Highest Oxidation State**:
- The oxidation state is determined by the number of electrons that can be lost.
- In configuration B (3d⁵ 4s²), the maximum oxidation state is +7 (losing all 5 d electrons and 2 s electrons).
- Other configurations do not provide a higher oxidation state than +7.

5. **Conclusion**:
- Therefore, the electronic configuration associated with the highest stable oxidation state is **B: 3d⁵ 4s²**.

### Final Answer:
**The electronic configuration associated with the highest stable oxidation state is 3d⁵ 4s².**

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