Which of the following bonds is the strongest ? .

Options

A. `I-I`
B. `F -F`
C. `H -H`
D. `O-O`

Explanation

To determine which of the given bonds is the strongest, we need to analyze the bonds mentioned: Iodine-Iodine (I-I), Fluorine-Fluorine (F-F), Hydrogen-Hydrogen (H-H), and Oxygen-Oxygen (O-O).

### Step-by-Step Solution:

1. **Evaluate Iodine-Iodine (I-I) Bond:**
- Iodine is a large atom, which means it has a larger atomic radius. This results in a weaker bond due to the increased distance between the nuclei of the two iodine atoms.
- **Conclusion:** The I-I bond is not the strongest.

2. **Evaluate Fluorine-Fluorine (F-F) Bond:**
- Fluorine has a very high electronegativity, which means it strongly attracts electrons. This can lead to instability in the bond due to the high electron repulsion between the two fluorine atoms.
- **Conclusion:** The F-F bond is also not the strongest.

3. **Evaluate Oxygen-Oxygen (O-O) Bond:**
- The O-O bond is a single bond with a lower percentage of s character (25% s character from sp³ hybridization). This lower s character means the bond is relatively weaker compared to bonds with higher s character.
- **Conclusion:** The O-O bond is weaker than the H-H bond.

4. **Evaluate Hydrogen-Hydrogen (H-H) Bond:**
- The H-H bond is formed by the overlap of two 1s orbitals, which means it has 100% s character. Bonds with higher s character tend to be stronger due to the closer proximity of the bonding electrons to the nucleus.
- **Conclusion:** The H-H bond is the strongest among the bonds discussed.

### Final Answer:
The strongest bond among the given options is the **Hydrogen-Hydrogen (H-H) bond**.

---