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What percentage of car exhaust is unburnt fuel?

if you know that, this would be great as well:

% of coal power plant emissions that is unburnt fuel

It really depends upon whether the engine is burning a ‘rich’ or a ‘weak’ mixture of petrol and air. A mixture about 10% rich in fuel gives the most power, whilst the most efficient running occurs with a weak mixture. Unburnt fuel in the form of carbon monoxide occurs in either case but with a weak mixture there is very little CO; a rich mixture, on the other hand, can give rise to as much as 3% unburnt CO.

This entry was posted on Friday, October 30th, 2009 at 8:10 pm and is filed under fuel emission. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.

One Response to “What percentage of car exhaust is unburnt fuel?”

  1. clausiusminkowski on October 31st, 2009 at 1:53 am

    It really depends upon whether the engine is burning a ‘rich’ or a ‘weak’ mixture of petrol and air. A mixture about 10% rich in fuel gives the most power, whilst the most efficient running occurs with a weak mixture. Unburnt fuel in the form of carbon monoxide occurs in either case but with a weak mixture there is very little CO; a rich mixture, on the other hand, can give rise to as much as 3% unburnt CO.
    References :

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