Assertion: Photochemical smog is oxidising in nature.
Reason: Photochemical smog contains `NO_(2)` and `O_(3)` which are formed during the sequence of reactions.

Options

A. Both A and R are correct and R is the correct explanation of A
B. Both A and R are correct and R is not the correct explanation of A
C. Both A and R are not correct
D. A is not correct but R is correct

Explanation

To solve the assertion-reason question regarding photochemical smog, we will break down the information step by step.

### Step 1: Understand the Assertion
The assertion states that "Photochemical smog is oxidizing in nature."
- Photochemical smog is a type of air pollution that occurs in urban areas, particularly during warm weather. It is characterized by the presence of various pollutants, including nitrogen oxides and ozone.

### Step 2: Understand the Reason
The reason provided is that "Photochemical smog contains NO₂ and O₃ which are formed during the sequence of reactions."
- NO₂ (nitrogen dioxide) and O₃ (ozone) are significant components of photochemical smog. Their formation is linked to the reactions that occur in the presence of sunlight.

### Step 3: Explain the Formation of Ozone
- In the presence of sunlight, nitrogen dioxide (NO₂) can break down to form nitric oxide (NO) and atomic oxygen (O).
- This atomic oxygen is highly reactive and can react with diatomic oxygen (O₂) in the atmosphere to form ozone (O₃).

### Step 4: Identify the Oxidizing Nature
- Ozone (O₃) is known to be a strong oxidizing agent.
- Therefore, the presence of ozone in photochemical smog contributes to its oxidizing nature.

### Step 5: Conclusion
- Since both the assertion and the reason are correct, and the reason explains why photochemical smog is oxidizing in nature, we can conclude that:
- Both the assertion and reason are correct, and the reason is the correct explanation of the assertion.

### Final Answer
- The correct option is A: Both assertion and reason are correct, and reason is the correct explanation of the assertion.

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