Environmental Engineering – Multiple Choice Questions (MCQs)

1. 13. Which gas is primarily produced during anaerobic digestion of sludge?

   • A. Oxygen
   • B. Carbon dioxide
   • C. Methane
   • D. Nitrogen

2. 14. What is "COD" in environmental engineering?

   • A. Chemical Oxygen Demand
   • B. Carbon Oxidation Degree
   • C. Chlorine Ozone Disinfection
   • D. Contaminant Organic Disposal

3. 15. Which of the following is a greenhouse gas?

   • A. Oxygen
   • B. Nitrogen
   • C. Carbon dioxide
   • D. Argon

4. 16. The major component of air pollution from vehicle exhaust is:

   • A. Oxygen
   • B. Nitrogen
   • C. Carbon monoxide
   • D. Water vapor

5. 17. What is the primary cause of acid rain?

   • A. Volcanic eruptions
   • B. Emissions of sulfur dioxide and nitrogen oxides
   • C. Excessive rainfall
   • D. Forest fires

6. 18. The layer of the atmosphere that protects us from harmful UV radiation is the:

   • A. Troposphere
   • B. Stratosphere
   • C. Mesosphere
   • D. Thermosphere

7. 19. What does "PM2.5" refer to in air quality?

   • A. Particulate matter with a diameter less than 2.5 micrometers
   • B. Pollution Measurement at 2.5 meters
   • C. Pure Methane at 2.5% concentration
   • D. Pressure Measurement at 2.5 Pascals

8. 20. Which device is used to remove particulate matter from industrial exhaust gases?

   • A. Scrubber
   • B. Electrostatic precipitator
   • C. Cyclone separator
   • D. All of the above

9. 21. What is "Noise Pollution"?

   • A. Unwanted or excessive sound that can disturb human or animal life
   • B. Sound used for communication
   • C. Sound in music
   • D. Sound in nature

10. 22. The unit for measuring noise level is:

    • A. Joules
    • B. Watts
    • C. Decibels (dB)
    • D. Meters

11. 23. Which of the following is a method of solid waste disposal?

    • A. Landfilling
    • B. Incineration
    • C. Composting
    • D. All of the above

12. 24. What is the "3 R's" principle in waste management?

    • A. Reduce
    • B. Reuse
    • C. Recycle
    • D. Remove