Environmental Engineering Multiple Choice Questions on “Air Pollutants”.
1. Which gas is mainly produced due to incomplete burning of wood?
a) CO
b) SO2
c) NO2
d) NO3
Answer: a
Clarification: CO is the colorless, odorless, toxic gas produced due to incomplete burning of wood.
2. Which of the following is involved in production of carboxy haemoglobin?
a) CO
b) SO2
c) NO2
d) NO3
Answer: a
Clarification: CO + Blood ——> Carboxy haemoglobin (Pink color).
3. Which of the following is a liquid form of aerosol?
a) Fume
b) Dust
c) Mist
d) Smoke
Answer: c
Clarification: Mist is a liquid form of aerosol whereas, Fume, Dust and Smoke are a solid form of aerosol.
4. X ray films are a source of which of the following gas?
a) SO2
b) CO2
c) NO2
d) SO3
Answer: c
Clarification: NO2 is produced from X ray film. It causes irritation to eyes and cause respiratory disease.
5. The maximum size of fly ash is ___________
a) 1μm
b) 100μm
c) 1000μm
d) 10μm
Answer: c
Clarification: Fly ash is a finely divided particle produced from the combustion of coal. Its maximum size is 1000μm.
6. Which of the following leads to a disease called broncho spasm?
a) SO2
b) SO3
c) SO4
d) CO2
Answer: b
Clarification: SO3 reacts with body fluids forming H2SO4 leading to Broncho spasm.
7. The minimum size of the smoke particle is ___________
a) 0.2μm
b) 1μm
c) 0.8μm
d) 0.5μm
Answer: d
Clarification: Smoke is produced due to incomplete combustion of coal. Its size lies between 0.5μm to 1μm.
8. Which of the following is a secondary air pollutant?
a) SPM
b) PAN
c) SO2
d) NO2
Answer: b
Clarification: Peroxy Acetyl Nitrate is a secondary air pollutant whereas, Suspended Particulate Matter, SO2 and NO2 are primary air pollutants.
9. The permissible concentration of PM 10 in the air is ___________
a) 60μg/m3
b) 40μg/m3
c) 50μg/m3
d) 20μg/m3
Answer: a
Clarification: The permissible concentration of PM 10 in air is 60μg/m3 whereas of PM 2.5 is 40μg/m3.