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Rate of displacement of individual gas molecule help

  1. Jan 24, 2012 #1
    Has anyone made a calculation for example, how much (or the mean) time it takes for an individual gas molecule to be displaced a distance of one meter (measured straight) from its original location?

    For example, air molecule at ambient pressure with a mean free path of 68 nm. That would be an incredible amount of collisions before it reaches 1 meter from its initial location.

    I can't find any such info in google and I'm not in the field of chemistry.

    Could anyone give me a mean figure, appreciate it!
  2. jcsd
  3. Jan 24, 2012 #2


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    Read up on random walks and diffusion. These topics should give you some idea of how to make that calculation.
  4. Jan 24, 2012 #3
    Thank you, well, I don't actually need a 'precise' value of the mean.

    If you're saying that diffusion gives a good approximation of the speed, then that is good enough for me.
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