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Homework Help: Blowing up hydrogen and oxygen falls under what?

  1. Oct 13, 2006 #1
    A hearty hello to all you admirable brainiacs. As this is my first post here it not coincidentally asks advice. I'm interested in creating a propulsion system fueled by hydrogen. I understand that hydrogen mixed with oxygen is explosive, but I need to calculate the exact amount of energy which can be derived from named explosion. I don't know what field of study besides mathematics contains the answer to my quandary. Is it rocket science that I need to look into? Or is it chemistry? I have a feeling it is both, but I don't know under what heading to look.

    A more practical explanation of my question: If I had 1 mol of H2. (Hydrogen gas), how much energy can be produced in combustion? And then from energy how much kinetic energy can be produced on an object weighing x.

    If my question is not clear please say so. Thanks in advance,

    The Third Anti-Christ.:devil:
  2. jcsd
  3. Oct 13, 2006 #2


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    (or do you homework for you, sly)
  4. Oct 14, 2006 #3


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    If you have 1 mol of H2, you need 1/2 mol O2. Look up the enthalpy values of H2, O2, and H2O, and you can calculate how much energy you can theoretically get (I assume here you've dealt with enthalpy).

    It's not the best estimate, but it's really simple
  5. Oct 14, 2006 #4


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    This is a standard chemistry problem, and yes hydrogen can be explosively combustible, but it is the source of energy in LH2/LOX (liquid) propuslion systems like the Space Shuttle Main Engine, which actually uses a hydrogen rich mixture to increase specific impluse.

    There is not need to develop a hydrogen propulsion since it already exists. Fuel cells also use hydrogen oxidation, but in a non-explosive process.
  6. Oct 14, 2006 #5
    Erroneous on both accounts!

    Do you mean enthropy? I've never delt with enthalpy, but I'll look into it.

    True, but it is hard to build a rocket like propulsion system with electricity. (Correct me if I'm wrong). I think I need either the LH2 or the hydrogen combustion. But I must be able to calculate trajectories and distances, which is why I am asking guidance.

    Thanks to everyone except Pythagorean,
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