250+ TOP MCQs on Air Pollution – Sources – 2 and Answers

Environmental Science Multiple Choice Questions on “Air Pollution – Sources – 2”.

1. What is the residence time (average time a particle is active in a given system) of carbon monoxide?
a) 11-15 years
b) 0.1-0.3 years
c) 0.5 years
d) Few minutes
Answer: b
Clarification: The residence time is the average time a particle remains active in a given system.

2. Which of the following gases has the highest affinity for blood haemoglobin?
a) Carbon dioxide
b) Oxygen
c) Carbon monoxide
d) Nitrogen
Answer: c
Clarification: It has 200 times greater affinity for haemoglobin than oxygen.

3. At what concentration can the taste and smell of sulphur dioxide be detected?
a) 1000-2000ppm
b) 11-30ppm
c) 500-700ppm
d) 0.1-0.3ppm
Answer: d
Clarification: Sulphur dioxide has a pungent odour which can be detected in even in very minute concentrations in the range of 0.1 – 0.3 parts per million.

4. Which is the major source for sulphur dioxide?
a) Volcanic eruptions
b) Coal and crude oil combustion
c) Burning of petrol
d) Sewage treatment process
Answer: b
Clarification: Though emission of sulphur dioxide is peak during volcanic eruptions, its major source is during combustion of crude oil and coal for heat and power generation.

5. Which is the largest source for production of nitrous oxide?
a) Chemical industry
b) Fertiliser industry
c) Fossil fuel combustion
d) Bacterial action
Answer: d
Clarification: Denitrifiers (such as ammonia oxidising bacteria) in aerobic conditions serve as the major producer for nitrous oxide.

6. Pesticides also contribute to air pollution along with polluting underground reservoirs.
a) True
b) False
Answer: a
Clarification: The method of spraying pesticides leads to small portion of pesticide serving as an air pollutant. Some pesticides evaporate from soil and pollute the air. Eg. DDT.

7. Which of the following are sources to fluorine air pollution?
a) Coal combustion
b) Steel industries
c) Phosphate fertiliser manufacturing
d) All of the mentioned
Answer: d
Clarification: Phosphate rock (Fluorapatite) is used for manufacturing of fertilisers and contributes to fluorine air pollution along with steel industries and coal combustion.

8. Which is/are the most significant air-borne allergen(s)?
a) Fungi
b) Pollen
c) Soot
d) All of the mentioned
Answer: b
Clarification: Pollen grains are the most significant air-borne allergen with an indestructible outer membrane, and are known to cause severe respiratory problems when inhaled.

9. Which of the following is a source for boron air pollution?
a) Rockets and jets
b) Automobiles
c) Soap industries
d) Refrigerants
Answer: a
Clarification: Borane is mixed with petroleum and used as a fuel in rockets and jets which when combusted releases boron which causes air pollution.

10. Which are the sources of arsenic pollution?
a) Coal and petroleum
b) Detergents and pesticides
c) Mine tailings
d) All of the mentioned
Answer: d
Clarification: Arsenic is a human carcinogen and is emitted during the combustion of coal and petroleum. It is also found in detergents, pesticides and mine tailings.

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