Question

Assertion: Suspended particulate matter (SPM) is an important pollutant released by diesel vehicles.
Reason: Catalytic converters greatly reduce pollution caused by automobiles.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion.
B. Both Assertion and Reason are correct and Reason is not the correct explanation for Assertion.
C. Assertion is correct but Reason is incorrect.
D. Both Assertion and Reason are incorrect.

Answer 1

Hint: Suspended particulate matter (SPM) are microscopic particles of solid or liquid matter suspended in the air. The sources can be natural or anthropogenic. They negatively impact the climate and precipitation, which adversely affect human health, thereby causing breathing problems and others.

Complete Answer:
- Particulates or SPM are the most harmful form of air pollution. Naturally occurring particulates include those originating from volcanoes, forest, dust storms, grassland fires, living vegetation, and sea spray. Human activities, like the burning of fossil fuels in vehicles, stubble burning, road dust, power plants, wet cooling towers in cooling systems, and many industrial processes, also generate significant amounts of particulates.

- Inhalation of these matters can cause health problems like lung cancer, asthma, other respiratory diseases, cardiovascular diseases, birth defects, premature delivery, and premature death. Apart from this, they can also block the stomatal openings of plants and interfere with photosynthesis functions. In this manner, high particulate matter concentrations in the atmosphere can lead to growth stunting or mortality in some plant species.

- A catalytic converter is an exhaust emission control machine that reduces toxic gases and pollutants in exhaust gas from an internal combustion engine into less-toxic pollutants by catalyzing a redox reaction. They are usually used with internal combustion engines fueled by either gas or diesel, including lean-burn engines and kerosene heaters and stoves. They are also used on electrical generators, mining equipment, locomotives, trucks, buses, motorcycles, and ships. Catalytic converters reduce the pollution caused by automobiles and other machines.

Both the assertion and reason are correct but the reason is not the correct explanation for the assertion. Hence, the correct option is B.

Note: Because of health and environmental concerns, most industries are required to install and operate some kind of dust collection system to control particulate emissions. Systems like cyclonic separators, fabric filter collectors (baghouses), wet scrubbers, and electrostatic precipitators, etc. are used to filter the polluted air. Apart from this, it can also be cleaned in the open air.