The lowest O-O bond length in the following molecule is :

Options

A. `O_(2)F_(2)`
B. `O_(2)`
C. `H_(2)O_(2)`
D. `O_(3)`

Answer

To determine the lowest O-O bond length among the given molecules, we will analyze the bond lengths based on bond order and the influence of electronegativity.

### Step-by-Step Solution:

1. **Identify the Molecules**: The molecules we need to consider are O2 (dioxygen), O2F2 (difluorooxygen), H2O2 (hydrogen peroxide), and O3 (ozone).

2. **Determine Bond Order**:
- **O2**: The bond order is 2 (double bond).
- **O2F2**: The presence of fluorine, which is highly electronegative, affects the bond. The bond order remains 2, but the bond length is reduced due to the electronegativity of fluorine.
- **H2O2**: The bond order is 1 (single bond).
- **O3**: The bond order is 1.5 (resonance structure).

3. **Analyze Electronegativity Effects**:
- Fluorine is the most electronegative element, and its presence in O2F2 pulls electron density away from the O-O bond, leading to a shorter bond length compared to O2.
- In H2O2, the O-O bond is longer due to the single bond character, and in O3, the bond length is intermediate due to resonance.

4. **Compare Bond Lengths**:
- O2 has a bond length associated with a double bond.
- O2F2 has a shorter bond length due to the influence of electronegative fluorine.
- H2O2 has the longest bond length due to the single bond.
- O3 has a bond length shorter than H2O2 but longer than O2F2.

5. **Conclusion**: Based on bond order and the effects of electronegativity, O2F2 has the lowest O-O bond length due to the strong pull of the fluorine atoms on the electron density, leading to a stronger and shorter bond.

### Final Answer:
The lowest O-O bond length is found in O2F2.