Practicing Success

Target Exam

CUET

Subject

Biology

Chapter

Environmental Issues

Question:

Assertion: Through the use of catalytic converters, unburnt hydrocarbons are changed into carbon monoxide which in turn is changed into nitrogen oxides and water.
Reason: Motor vehicles equipped with catalytic converters should use leaded petrol to protect the catalyst from degradation.

Options:

Both Assertion (A) and reason (R) are correct and R is the correct explanation of A.

Both Assertion (A) and reason (R) are correct and but R is not the correct explanation of A.

Assertion (A) is true but Reason (R) is not correct.

Both Assertion (A) and Reason are false (F ).

Correct Answer:

Both Assertion (A) and Reason are false (F ).

Explanation:

The correct answer is Option (4) –Both Assertion (A) and Reason are false (F ).

A catalytic converter is a vehicle emissions control device that converts toxic pollutants of the exhaust gas into less toxic pollutants by catalyzing a redox reaction. Catalytic converters, having expensive metals namely platinum, palladium and rhodium as catalysts, are fitted into automobiles for reducing emission of poisonous gases. Rhodium is used as reduction catalyst, palladium is used as an oxidation catalyst, and platinum is used both for oxidation and reduction. As the exhaust passes through the catalytic converter, unburnt hydrocarbons are converted into carbon dioxide and water, and carbon monoxide and nitric oxide are changed to carbon dioxide and nitrogen gas, respectively. Motor vehicles equipped with catalytic converter should use unleaded petrol because lead in the petrol inactivates the catalyst.