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[A] : Suspended particulate matter (SPM)...

[A] : Suspended particulate matter (SPM) is an important pollutant released by diesel vehicles .
[R] : Catalytic converters greatly reduce pollution caused by automobiles .

A

If both Assertion & Reason are true and the reason is the correct explanation of the assertion, then mark a

B

lf both Assertion & Reason are true but the reason is no t the correct explanation of the assertion, then mark b

C

If Assertion is true statement but Reason is false, then mark c

D

If both Assertion and Reason are false statements, then mark d.

Text Solution

Verified by Experts

The correct Answer is:
B
SPM (Suspended Particulate Matter) is defined as particles floating in the air with a diameter below 10 `mu m.` Studies have shown that high SPM concentrations in the air can have detrimental impact on respiratory organs. SPM is generated from natural sources (e.g., volcanoes or dust stoms) and human activities (vehicles, incinerators and industrial plants).

Catalytic converter is a device designed to reduce the amount of emissions from automobiles. The current (so-called three-way) systems use heated metal catalyst to reduce the emissions of carbon monoxide (CO), hydrocarbons, and nitric oxide (NO) all of which contribute to the formation of photochemical smog. In an automobile's exhaust system, a catalytic converter provides an environment for a chemical reaction where unburnt hydrocarbons completely combust. Hence the combustion process continues but outside the engine combustion chamber where no useful energy is extracted. Toxic car gases such as unburnt hydrocarbon (UHC) and carbon monoxide (CO) would not exst if the fuel to energy conversion in the engine were perfect.
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