Discussion
Arrange the formation of photochemical smog in causal order:
1. Oxides of nitrogen and organic compounds are emitted by traffic
2. Sunlight drives reaction between the precursors
3. Ozone and secondary aerosol accumulate through the day
4. Concentrations peak in the afternoon downwind of the city
Select the correct sequence.
Answer: C
Correct answer: 1, 2, 3, 4
The chain runs from emission to observed peak. Traffic emits oxides of nitrogen and volatile organic compounds (1), chiefly during the morning rush. Sunlight then drives the radical chemistry that converts nitric oxide to nitrogen dioxide without consuming ozone (2).
Ozone and secondary aerosol accumulate through the day as that chemistry proceeds (3), and because the air mass is moving while it reacts, concentrations peak in the afternoon downwind of the city (4). That displacement is characteristic - suburban and rural sites downwind often record higher ozone than the city centre that emitted the precursors.
Post your comment
Please log in or register to post a comment.
Examination Categories
- SSC Exams
- Banking Exams
- Teaching Exams
- Civil Services Exams
- Railways Exams
- Engineering Recruitment Exams
- Defence Exams
- State Government Exams
- Police Exams
- Insurance Exams
- Nursing Exams
- Other Government Exams
- NRA CET
- PG Entrance Exams
- Campus Placement
- MBA Entrance Exams
- CUET and UG Entrance
- Judiciary Exams
- Regulatory Body Exams
- Software Development