Ozone is :

Options

A. primary pollutant
B. secondary pollutant
C. natural pollutant
D. none of the above

Answer

**Step-by-Step Solution:**

1. **Definition of Ozone:**
- Ozone is a molecule composed of three oxygen atoms, represented chemically as O₃.

2. **Classification of Ozone:**
- Ozone is classified as a secondary pollutant. This means it is not directly emitted into the atmosphere but is formed through chemical reactions.

3. **Reason for Being a Secondary Pollutant:**
- Ozone is produced in a cycle of reactions involving other pollutants, rather than being released directly from a source.

4. **Involved Compounds:**
- The formation of ozone involves two main classes of compounds:
- **Nitrogen Oxides (NOx):** This includes nitric oxide (NO) and nitrogen dioxide (NO₂).
- **Hydrocarbons:** These are organic compounds that contain hydrogen and carbon.

5. **Understanding Primary Pollutants:**
- Primary pollutants are substances that are emitted directly from a source into the atmosphere. Since ozone is not directly emitted, it does not fall under this category.

6. **Understanding Natural Pollutants:**
- Natural pollutants are those created by natural processes, such as volcanic eruptions or sea salt particles. Ozone is not classified as a natural pollutant.

7. **Conclusion:**
- Based on the classifications and definitions, the correct answer to the question "Ozone is:" is that it is a **secondary pollutant**.

**Final Answer:**
Ozone is a secondary pollutant.

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