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 can analyze the given configurations step by step.

### Step 1: List the Given Electronic Configurations
The electronic configurations provided are:
1. \( \text{Ar} \, 3d^1 \, 4s^2 \)
2. \( \text{Ar} \, 3d^5 \, 4s^1 \)
3. \( \text{Ar} \, 3d^5 \, 4s^2 \)
4. \( \text{Ar} \, 3d^6 \, 4s^1 \)

### Step 2: Understand Stability of Electronic Configurations
- Half-filled and fully filled d-orbitals are more stable than partially filled d-orbitals.
- A fully filled d-orbital configuration is represented as \( d^{10} \).
- A half-filled d-orbital configuration is represented as \( d^5 \).

### Step 3: Analyze Each Configuration
1. **Configuration 1: \( \text{Ar} \, 3d^1 \, 4s^2 \)**
- The \( 4s \) orbital is fully filled, but the \( 3d \) orbital is only partially filled. This configuration is not very stable.

2. **Configuration 2: \( \text{Ar} \, 3d^5 \, 4s^1 \)**
- The \( 3d \) orbital is half-filled, and the \( 4s \) orbital is partially filled. This configuration is more stable than the first one.

3. **Configuration 3: \( \text{Ar} \, 3d^5 \, 4s^2 \)**
- Here, the \( 3d \) orbital is half-filled, and the \( 4s \) orbital is fully filled. This configuration is very stable due to the half-filled \( 3d \) and fully filled \( 4s \).

4. **Configuration 4: \( \text{Ar} \, 3d^6 \, 4s^1 \)**
- The \( 3d \) orbital is partially filled, and the \( 4s \) orbital is partially filled. This configuration is less stable than the third one.

### Step 4: Conclusion
Among the configurations analyzed, the configuration \( \text{Ar} \, 3d^5 \, 4s^2 \) is associated with the highest stable oxidation state due to its fully filled \( 4s \) orbital and half-filled \( 3d \) orbital.

### Final Answer
The electronic configuration associated with the highest stable oxidation state is:
**\( \text{Ar} \, 3d^5 \, 4s^2 \)**

---