The common refrigerant chlorofluoromethane (freon) and `NO_(2)` are serious pollutants because they :

Options

A. Destroys haemoglobin
B. Disrupts ozone layer
C. Lowers atmospheric temperature
D. Prevents cloud condensation

Answer

### Step-by-Step Solution:

1. **Identify the Pollutants**: The question mentions two specific pollutants: chlorofluoromethane (commonly known as Freon) and nitrogen dioxide (NO2).

2. **Understand the Nature of Freon**: Freon is a gas that is tasteless and odorless. It is primarily used as a refrigerant in cooling systems.

3. **Recognize the Toxicity**: Both Freon and NO2 are toxic substances. Freon can be harmful to human health and the environment.

4. **Explore the Impact on the Atmosphere**: When released into the atmosphere, Freon and NO2 can undergo reactions, especially when exposed to sunlight.

5. **Chemical Reactions**: The presence of sunlight causes these gases to break down, leading to the release of oxygen atoms. These oxygen atoms can then react with ozone (O3) in the stratosphere.

6. **Disruption of the Ozone Layer**: The reaction between the released oxygen atoms and ozone results in the depletion of the ozone layer, which is crucial for protecting life on Earth from harmful ultraviolet (UV) radiation.

7. **Conclusion**: Therefore, the common refrigerant Freon and NO2 are serious pollutants because they disrupt the ozone layer, which is essential for maintaining a safe environment.

### Final Answer:
The common refrigerant chlorofluoromethane (Freon) and NO2 are serious pollutants because they disrupt the ozone layer.

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