The bond energies of `F_(2),Cl_(2),Br_(2)` and `I_(2)` are 155.4, 243.6, 193.2 and `151.2 Kjmol^(-1)` respectively. The strongest bond is :

Options

A. F-F
B. Cl-Cl
C. Br-Br
D. I-I

Answer

To determine which bond among `F_(2)`, `Cl_(2)`, `Br_(2)`, and `I_(2)` is the strongest, we need to analyze the bond energies provided for each molecule:

1. **Identify the bond energies:**
- For `F_(2)`, the bond energy is **155.4 kJ/mol**.
- For `Cl_(2)`, the bond energy is **243.6 kJ/mol**.
- For `Br_(2)`, the bond energy is **193.2 kJ/mol**.
- For `I_(2)`, the bond energy is **151.2 kJ/mol**.

2. **Understanding bond energy:**
- Bond energy is defined as the amount of energy required to break one mole of bonds in gaseous molecules. A higher bond energy indicates a stronger bond.

3. **Compare the bond energies:**
- Now, we will compare the bond energies:
- `F_(2)`: 155.4 kJ/mol
- `Cl_(2)`: 243.6 kJ/mol
- `Br_(2)`: 193.2 kJ/mol
- `I_(2)`: 151.2 kJ/mol

4. **Identify the strongest bond:**
- Among the bond energies listed, `Cl_(2)` has the highest bond energy at **243.6 kJ/mol**. This indicates that the chlorine-chlorine bond is the strongest of the four bonds.

5. **Conclusion:**
- Therefore, the strongest bond is the **chlorine-chlorine bond** in `Cl_(2)`.

### Summary of Steps:
1. Identify and list the bond energies for each molecule.
2. Understand the concept of bond energy and its relation to bond strength.
3. Compare the bond energies to determine which is the highest.
4. Conclude that the bond with the highest energy corresponds to the strongest bond.