A catalytic converter fitted in the exhaust of a car

changes carbon monoxide, unburnt hydrocarbons and nitrogen oxides into less harmful gasesCorrect answerYour answermakes the engine produce more powerCorrect answerYour answerremoves the sound of the engineCorrect answerYour answerturns carbon dioxide into oxygenCorrect answerYour answer

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CorrectNot quiteAnswer A

Correct answer: A

Metals such as platinum and rhodium in the converter speed up reactions in the hot exhaust.
Carbon monoxide and hydrocarbons become carbon dioxide and water, and nitrogen oxides become nitrogen.

Worth noting

It still gives out carbon dioxide; it cannot turn it back into oxygen. Leaded petrol ruins the catalyst.

Concept: Catalytic converters
Typical timeTypical: 35 s
Your timeYours: —

The rule this testsAir, water, soil and noise pollution

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A catalytic converter fitted in the exhaust of a car

Explanation