Which of the following molecule is theoretically not possible ?

Options

A. `SF_(4)`
B. `OF_(2)`
C. `OF_(4)`
D. `O_(2)F_(2)`

Answer

To determine which of the given molecules is theoretically not possible, we need to analyze the oxidation states of the elements involved in each molecule.

### Step-by-Step Solution:

1. **Identify the Molecules**: We have four options to consider: SF4, OF2, OF4, and O2F2.

2. **Analyze Each Molecule**:
- **SF4 (Sulfur Tetrafluoride)**:
- Sulfur can have oxidation states of +4 or +6. In SF4, sulfur is in the +4 oxidation state, which is possible.
- **OF2 (Oxygen Difluoride)**:
- In OF2, oxygen is in the -2 oxidation state (as fluorine is more electronegative and takes -1 for each fluorine). This is a valid oxidation state for oxygen.
- **OF4 (Oxygen Tetrafluoride)**:
- In OF4, oxygen would need to have a +4 oxidation state (as each fluorine is -1). However, oxygen typically has oxidation states of -2, -1, +1, and +2. A +4 oxidation state is not a common or stable oxidation state for oxygen, making this molecule theoretically impossible.
- **O2F2 (Dioxygen Difluoride)**:
- In O2F2, each oxygen can have an oxidation state of -1 (as each fluorine is -1). This is also a valid configuration.

3. **Conclusion**:
- After analyzing the oxidation states, we find that OF4 is the only molecule that cannot exist theoretically due to the +4 oxidation state of oxygen, which is not feasible.

### Final Answer:
The molecule that is theoretically not possible is **OF4** (Option 3).

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