Question

Which of the following is not formed during Photochemical smog formation?

• A. Ozone
• B. Aldehydes
• C. Peroxy acetyl nitrate
• D. Sulphuric Acid

Hint:

Sulphuric acid belongs to the classical, sulphur-based smog.

Answer 1

The Correct Option is D

Step 1: Understanding the Concept:
The passage says photochemical smog contains ozone, PAN and formaldehyde. These are secondary pollutants made from sunlight reactions.

Step 2: Key Approach:
Find the product that belongs to classical smog instead.

Step 3: Check option (1).
Ozone forms when nitrogen dioxide splits in light and the free oxygen atom joins O2. So ozone is formed. (1) is not the answer.

Step 4: Check option (2).
Aldehydes such as formaldehyde form from hydrocarbon oxidation. They are formed. (2) is not the answer.

Step 5: Check option (3).
Peroxy acetyl nitrate (PAN) forms from radicals and nitrogen dioxide. It is formed. (3) is not the answer.

Step 6: Check option (4).
Sulphuric acid comes from sulphur dioxide in coal smoke, which is classical smog. So it is not a photochemical smog product. (4) is the answer.

Final Answer:
Sulphuric acid is not formed, so the answer is option 4.
\[ \boxed{4} \]