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Homework Help: Hydrogen + oxygen model rockets

  1. Sep 19, 2012 #1
    1. The problem statement, all variables and given/known data
    Could one expect to get a good thrust off oxygen and hydrogen fuel in a gaseous form, pumped at ~60 PSI into a 2 liter container? How much (in terms of mass) oxygen and hydrogen would be in the said container at such a pressure, assuming we have a 2/1 hydrogen/oxygen ratio in terms of moles? How did you calculate the amount in question?

    2. Relevant equations

    3. The attempt at a solution
    I tried to use the ideal gas law, but it doesn't' seem to apply when there's a 2/1 molar mix of two gases in one container.
  2. jcsd
  3. Sep 19, 2012 #2
    Are you familiar with the concept of partial pressure?
  4. Sep 19, 2012 #3


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    I think another word for a pressurized container filled with a mixture of hydrogen and oxygen gas would be a "bomb".
  5. Sep 19, 2012 #4
    It's a fuel tank. The fuel (oxygen and hydrogen) will be directed into a combustion chamber automatically, due to the high pressure of the fuel tank. No offense, but by your logic, most liquid fuel boosters would also be bombs.
  6. Sep 19, 2012 #5
    Also, assuming that we fill a 2 liter container with hydrogen under a 20 psi pressure, would the hydrogen in the said container weight:


    m=113.137665678*1.007947 = 114.036770707 grams

    assuming the temperature is 293.15 degrees Kelvin?
  7. Sep 19, 2012 #6
    Convert liters to cubic meters.
  8. Sep 19, 2012 #7


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    Liquid fuel rockets store the fuel and oxidizer separately and only mix them in the combustion chamber. Mixing them in the storage container is a recipe for disaster. Perhaps I'm wrong - I'm not an expert in this area, but it sounds to me like you are on very dangerous ground.
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