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 bond is the strongest among the given options (I-I, Fluorine-Fluorine, Hydrogen-Hydrogen, and Oxygen-Oxygen), we will analyze the bond dissociation enthalpies of each bond.

### Step-by-Step Solution:

1. **Analyze the I-I Bond:**
- The I-I bond (Iodine-Iodine) is the weakest bond among the options.
- Reason: Iodine has a larger atomic size, leading to a longer bond length. A longer bond length generally correlates with weaker bonds.
- Bond dissociation enthalpy: 152 kJ/mol.

2. **Analyze the Fluorine-Fluorine Bond:**
- The F-F bond (Fluorine-Fluorine) has a bond length of 145 picometers.
- Reason: Fluorine atoms have lone pairs that cause repulsion, making the bond easier to break.
- Bond dissociation enthalpy: Approximately 156 kJ/mol.

3. **Analyze the Hydrogen-Hydrogen Bond:**
- The H-H bond (Hydrogen-Hydrogen) has a bond length of 74 picometers.
- Reason: Hydrogen atoms do not have lone pairs, and thus there is no repulsion affecting the bond strength.
- Bond dissociation enthalpy: 436 kJ/mol.

4. **Analyze the Oxygen-Oxygen Bond:**
- The O-O bond (Oxygen-Oxygen) has a double bond.
- Reason: Although oxygen has lone pairs like fluorine, the presence of a double bond increases the bond strength.
- Bond dissociation enthalpy: 498 kJ/mol, which is the highest among the options.

5. **Conclusion:**
- Comparing the bond dissociation enthalpies:
- I-I: 152 kJ/mol
- F-F: 156 kJ/mol
- H-H: 436 kJ/mol
- O-O: 498 kJ/mol
- The strongest bond among the given options is the **Oxygen-Oxygen bond**.

### Final Answer:
The strongest bond is the **Oxygen-Oxygen bond**.