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A question about water

  1. Aug 31, 2006 #1
    hydrogen is a combustible substance and oxygen is a supporter of combustion. but water extinguishes fire. how is that?:confused:
  2. jcsd
  3. Aug 31, 2006 #2


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    Staff: Mentor

    Water is the waste product of the combustion you are describing. It has already been burned.
  4. Aug 31, 2006 #3


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    Gold Member

    Uh, yeah. That pretty much covers it.

    Water is the "ash" left over from burning hydrogen.
    Last edited: Sep 1, 2006
  5. Sep 3, 2006 #4


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    Varsha: Please look up the definition of a "compound" in your chemistry text.

    To others: Something being a combustion product does not mean the thing is immune to further combustion (eg: CO, aldehydes), and that's besides the point here. Furthermore, water is most certainly nothing like an ash. An ash is the uncombusted residue; water is a combustion product.
    Last edited: Sep 3, 2006
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