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Speaker 1: Welcome to Brainstuff from how stuff works dot com where

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Speaker 1: smart happens. Hi Am Marshall Brain with today's question, what

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Speaker 1: is a catalytic converter and how does it work? A

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Speaker 1: catalytic converter is a device in your car that uses

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Speaker 1: a catalyst to convert three harmful compounds in car exhaust

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Speaker 1: into harmless compounds. The three harmful compounds are one hydrocarbons

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Speaker 1: in the form of unburned gasoline to carbon monoxide formed

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Speaker 1: by the combustion of gasoline, and three nitrogen oxides created

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Speaker 1: when the heat in the engine forces nitrogen in the

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Speaker 1: air to combine with oxygen. Carbon monoxide is a poison

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Speaker 1: for any air breathing animal. Nitrogen oxides lead to smog

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Speaker 1: and acid rain, and hydrocarbons produce smog. In a catalytic converter,

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Speaker 1: the catalyst, in the form of platinum and palladium, is

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Speaker 1: coated on to a ceramic honeycomb or ceramic beads that

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Speaker 1: are housed in a muffler like package attached to the

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Speaker 1: exhaust pipe. The catalyst helps to convert carbon monoxide into

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Speaker 1: carbon dioxide. It converts the hydrocarbons into carbon dioxide and water,

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Speaker 1: and it converts the nitrogen oxides back into nitrogen and oxygen.

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Speaker 1: This makes the exhaust coming out the exhaust pipe a

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Speaker 1: lot cleaner. Do you have any ideas or suggestions for

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Speaker 1: this podcast? If so, please send me an email at

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Speaker 1: podcast at how stuff works dot com. For more on

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Speaker 1: this and thousands of other topics, go to how stuff

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Speaker 1: works dot com