Smog is formed near the ground in the troposphere.
Nitrogen oxides impart yellow-brown colour to smog.
Photochemical somg formation is maximum when sun is overhead in the day.
Photochemical smog formation is maximum in winter compared to summer season.
Show Solution
The Correct Option isD
Solution and Explanation
Step 1: Idea behind the question:
The question asks which claim fails. Think about what photochemical smog needs: precursors and strong light.
Step 2: Look at the passage:
The passage names nitrogen oxides, volatile hydrocarbons and sunlight as the ingredients of Los Angeles smog. Light is the energy source.
Step 3: Test (1) and (2):
Statement (1) matches the passage, since smog sits near the ground. Statement (2) is also fine, because nitrogen oxides are brownish and colour the haze.
Step 4: Test (3):
At midday the sun is highest and the light is most intense. Reactions are quickest then, so the smog peak is at noon. This statement holds.
Step 5: Test (4):
Winter days have lower sun angle and less radiation. Less light means fewer photochemical reactions, so smog is worse in the warm season. This claim is the wrong one.
Step 6: Decide:
Only one statement is false, which is the winter claim.
Final Answer:
The incorrect statement is (4).
\[ \boxed{4} \]
