It is used in refrigerator and air conditioners and it is a source of `Cl^(-)` :

Options

A. Benzopyrene
B. Freon
C. Benzene
D. `CH_(4)`

Answer

To solve the question "It is used in refrigerator and air conditioners and it is a source of `Cl^(-)`", we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Context**: The question specifies that we are looking for a substance used in refrigerators and air conditioners that releases chlorine ions (Cl^-).

2. **Consider Common Refrigerants**: The most common substances used in refrigerators and air conditioning systems are refrigerants. One of the widely known refrigerants is Freon.

3. **Understand Freon**: Freon is a trade name for a group of chemicals known as chlorofluorocarbons (CFCs). CFCs are known for their ability to absorb heat, which makes them effective as refrigerants.

4. **Chlorine Ion Release**: CFCs, including Freon, release chlorine ions when they break down in the atmosphere. This release of chlorine is a significant factor in ozone layer depletion.

5. **Eliminate Other Options**: The question may present other substances (like benzopyrene, benzene, and methane).
- Benzopyrene is related to tobacco and is carcinogenic but not used in refrigeration.
- Benzene is an organic compound but not used as a refrigerant.
- Methane is produced by ruminants and is not relevant to refrigeration.

6. **Conclusion**: Based on the analysis, the correct answer is Freon, as it is specifically used in refrigerators and air conditioners and is a source of chlorine ions.

### Final Answer:
The correct answer is **Freon**.

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