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Homework Help: Can someone help me rank these?

  1. Jan 9, 2008 #1
    The problem asks me to rank from largest polluter to lowest (1 being highest and 4 being lowest.) There are diesel, E85, Gasoline, Gasoline with 20% ethanol.

    I know diesel will be 1 but then im kinda confused on which one pollutes more can anyone help me?
  2. jcsd
  3. Jan 11, 2008 #2


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    This is a nonsense question. Each kind of fuel generates different kinds and amounts of pollutants. Furthermore, each kind of engine can be equipped with a wide variety of pollution-mitigation devices. You'd have to be much more specific about what you mean.

    - Warren
  4. Jan 12, 2008 #3
    It depends if they are used in equal amounts, with the same vehicle. You can't really claim that one is a higher polluter than the other as it depends so greatly on how they are used, and what they are used for! Where was this question by the way?
  5. Jan 15, 2008 #4


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    You are right about diesel being #1. http://www.ucsusa.org/publications/catalyst/sp04-catalyst-diesel-or-gasoline-fuel-for-thought.html [Broken]

    For the others, you have to consider the effect of the oxygenate (ethanol) on the pollution produced. You can easily rank the remaining fuels based on the oxygenate content. It was once thought that http://sd.water.usgs.gov/nawqa/vocns/mtbe/bib/" [Broken] but you could argue they produce more pollution and be correct as well. You need to document your answer carefully.
    Last edited by a moderator: May 3, 2017
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