Mark the incorrect statement about chlorofluorocarbons.

Options

A. The balance between the production and degradation of ozone has been affected by CFCs.
B. CFCs are commonly used as refrigerants .
C. CFCs are broken down into Cl atoms by UV rays in the troposphere , from where they travel upwards to the stratosphere and degrade the ozone layer.
D. Cl atoms act as catalysts in the reaction, therefore they do not get consumed and continue to affect the ozone level.

Answer

To solve the question regarding the incorrect statement about chlorofluorocarbons (CFCs), we will analyze each statement provided in the question one by one.

### Step-by-Step Solution:

1. **Statement Analysis**:
- **Statement 1**: "The balance between the production and degradation of ozone has been affected by CFC."
- This statement is **true**. CFCs disrupt the natural balance of ozone production and degradation in the atmosphere.

2. **Statement 2**: "CFC are commonly used as refrigerants."
- This statement is also **true**. CFCs have been widely used in refrigeration and air conditioning systems.

3. **Statement 3**: "CFC are broken down into Cl atoms by UV rays in the troposphere from where they travel upwards to the stratosphere and degrade the ozone layer."
- This statement is **incorrect**. The breakdown of CFCs into chlorine atoms occurs primarily in the stratosphere, not in the troposphere. While CFCs may travel from the troposphere to the stratosphere, their degradation by UV rays happens in the stratosphere.

4. **Statement 4**: "Chlorine atoms act as catalysts in the reaction therefore they do not get consumed and continue to affect the ozone level."
- This statement is **true**. Chlorine atoms released from CFCs act as catalysts in ozone depletion, meaning they can participate in multiple reactions without being consumed.

### Conclusion:
The incorrect statement about chlorofluorocarbons is **Statement 3**.

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