Which of the following is a liquid?

Options

A. `F_2`
B. `Cl_2`
C. `Br_2 `
D. `I_2`

Explanation

To determine which of the following substances is a liquid, we need to analyze the states of the given substances based on their molecular size and intermolecular forces.

### Step-by-Step Solution:

1. **Identify the Substances**: The question asks us to identify which among the given options is a liquid. The substances mentioned are F2 (Fluorine), Cl2 (Chlorine), Br2 (Bromine), and I2 (Iodine).

2. **Analyze F2 (Fluorine)**:
- Fluorine is a small molecule.
- Due to its small size, the intermolecular distance is relatively large.
- The intermolecular forces are weak.
- Therefore, F2 exists in the gaseous state.

3. **Analyze Cl2 (Chlorine)**:
- Chlorine is also a small molecule, similar to fluorine.
- It has a larger intermolecular distance compared to larger molecules.
- The intermolecular forces are also weak.
- Thus, Cl2 exists in the gaseous state.

4. **Analyze Br2 (Bromine)**:
- Bromine is a medium-sized molecule.
- The intermolecular distance is moderate.
- The intermolecular forces are also moderate.
- Hence, Br2 exists in the liquid state.

5. **Analyze I2 (Iodine)**:
- Iodine is a larger molecule.
- The intermolecular distance is smaller due to the larger size.
- The intermolecular forces are strong.
- Consequently, I2 exists in the solid state.

6. **Conclusion**:
- Among the substances analyzed, only Br2 (Bromine) exists in the liquid state.

### Final Answer:
The liquid among the given options is **Bromine (Br2)**.

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