In which of the following is the highest oxidation state not possible?

Options

A. `[XeO_(6)]^(4-)`
B. `XeF_(8)`
C. `OSO_(4)`
D. `RuO_(4)`

Explanation

To determine in which of the given compounds the highest oxidation state is not possible, we will analyze each option step by step.

### Step 1: Analyze XeO6^4-
1. **Determine the oxidation state of Xenon (Xe)**:
- In the ion XeO6^4-, there are 6 oxygen atoms each contributing -2 (total -12).
- The overall charge of the ion is -4.
- Let the oxidation state of Xe be x.
- The equation becomes:
\[ x + 6(-2) = -4 \]
\[ x - 12 = -4 \implies x = +8 \]
2. **Conclusion**: The highest oxidation state of Xe in XeO6^4- is +8, which is possible.

### Step 2: Analyze XeF8
1. **Determine the oxidation state of Xenon (Xe)**:
- In the compound XeF8, there are 8 fluorine atoms each contributing -1 (total -8).
- Let the oxidation state of Xe be x.
- The equation becomes:
\[ x + 8(-1) = 0 \]
\[ x - 8 = 0 \implies x = +8 \]
2. **Steric hindrance**: However, having 8 fluorine atoms around a single xenon atom leads to steric hindrance, making this structure impractical.
3. **Conclusion**: While +8 is theoretically possible, the steric hindrance makes XeF8 not feasible.

### Step 3: Analyze OSO4
1. **Determine the oxidation state of Sulfur (S)**:
- In OSO4, there are 4 oxygen atoms each contributing -2 (total -8).
- Let the oxidation state of S be x.
- The equation becomes:
\[ x + 4(-2) = 0 \]
\[ x - 8 = 0 \implies x = +8 \]
2. **Conclusion**: The highest oxidation state of S in OSO4 is +8, which is possible.

### Step 4: Analyze RuO4
1. **Determine the oxidation state of Ruthenium (Ru)**:
- In RuO4, there are 4 oxygen atoms each contributing -2 (total -8).
- Let the oxidation state of Ru be x.
- The equation becomes:
\[ x + 4(-2) = 0 \]
\[ x - 8 = 0 \implies x = +8 \]
2. **Conclusion**: The highest oxidation state of Ru in RuO4 is +8, which is possible.

### Final Conclusion
After analyzing all the compounds, the only one where the highest oxidation state is not practically possible due to steric hindrance is **XeF8**. Therefore, the correct answer is:

**Option B: XeF8**

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