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Ionisation to cool gas

  1. Apr 6, 2009 #1
    If you use high voltage to rip electrons away from gas molecules thus forming ions will this have a cooling effect on the gas? Removing electrons from an atom must bring it to a lower energy state, will that lower energy state manifest itself as a lowering in temperature?

    Could you use this principle to cool an object?
  2. jcsd
  3. Apr 6, 2009 #2
    they have laser cooling i dont know if that quite what you are asking.
  4. Apr 6, 2009 #3
    I was thinking of its application to cool a jet of gas. Here is a quick sketch. Pressurised gas flows through a nozzle which has sharp points attached to a EHT. The electrons are ripped from the gas thus ionising it as it passes over the grid. Will the temperature of the gas be reduced?

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  5. Apr 6, 2009 #4
    usually when a plasma is created it gets hotter.
  6. Apr 6, 2009 #5

    A plasma would be created if you used a massive amount of electrical energy, considering the fact that we are dealing with gas at pressure. I however was just thinking about the production of ionised gas as opposed to a plasma state.
  7. Apr 6, 2009 #6
    perhaps you theory is to deep for me to comprehend and we need more expert opinions
  8. Apr 6, 2009 #7

    Andy Resnick

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    Why do you think ionizing an atom will lower its internal energy?
  9. Apr 7, 2009 #8
    E= MC2 matter is energy and you are removing matter (electrons) from the atom you must be reducing its energy level as you are reducing its mass?
  10. Apr 7, 2009 #9

    Andy Resnick

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    Are you implying that lighter objects are colder than heavier objects? Or that cutting an apple in half somehow cools the apple?
  11. Apr 7, 2009 #10

    No, I was answering your question, you asked why I thought ionizing an atom would reduce its energy. If you are removing matter from an atom are you not reducing its energy according to E=MC2 ??

    As for my thoughts to why this may cool a gas I have noticed that atoms/molecules tend to eject matter to lower their energy level. That matter could be in the from of photons or electrons but after this mater has been ejected the atom jumps down to a lower energy state. If that is so why wouldn't ripping electrons from an atom cause its energy state to be reduced (this applys to positive ions only)

    I am not saying positive ions are stable. If they are at a lover energy level then the environment they will obviously attract electrons to get to the same energy level as the environment and thus archive equilibrium.
  12. Apr 9, 2009 #11
    How are you planning to "rip" an electron away from a nucleus without giving the nucleus a BOOST in kinetic energy (and thus temperature)?
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