Question

Assertion: Suspended particulate matter(SPM) is an important pollutant released by the 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: A finely separated solid or liquid which, from combustion processes, manufacturing activities or natural sources, can be dispersed through the air is called as Suspended particulate matter (SPM).

Complete Answer:
- Microscopic solids or liquid matter suspended in the Earth's atmosphere are atmospheric particulate matter, also known as particulate matter (PM) or particulates. Particulate matter is the amount of all air-suspended solid and liquid particles, many of which are toxic. Both organic and inorganic particles, such as dust, pollen, soot, smoke, and liquid droplets, compose this complex mixture.
- As suspended particulate matter (SPM) is a significant contaminant emitted by diesel vehicles, the statement is correct. SPM is solid or liquid microscopic matter suspended in the atmosphere of the Earth. They are finely divided solids or liquids which, from combustion processes, industrial activities or natural sources, can be dispersed through the air. Dust , smoke, soot, pollen and soil particles contain particulate matter.
- The reason is right, as catalytic converters significantly reduce car pollution, is a system used to reduce internal combustion engine emissions, but the statement is not correctly stated.
- The size of suspended particles in the atmosphere ranges from a few nanometers to tens of micrometres, about four orders of magnitude. Through the break-up of larger solid particles, the largest particles, called the coarse fraction (or mode), are mechanically formed. Wind-blown dust from agricultural activities, uncovered dirt, unpaved roads or mining operations may be found in these particles.
- Road dust and air turbulence are created by traffic, which can stir up road dust. The evaporation of sea spray near coasts will create large particles. Everything in this wider size range are pollen grains, mould spores, and plant and insect parts.

The correct answer is option (B) Both assertion and reason are correct and reason is not explanation for assertion.

Note: In this way, high concentrations of particulate matter in the environment may contribute to growth stunting or mortality in certain plant organisms. Particulate matter may block plant stomatal openings and interfere with photosynthesis functions.