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Vapor Pressure and Atmospheric Pressure

  1. Oct 30, 2012 #1
    From what I have read so far, the vapor pressure of a liquid is temperature dependent while it is independent of the atmospheric pressure. I am not sure why atmospheric pressure would have no effect of the vapor pressure though. For example, if a highly volatile liquid is placed in a sealed container, and I increase the pressure inside the container to an extremely high value, wouldn't the high pressure make it harder for the volatile liquid to evaporate?
  2. jcsd
  3. Oct 30, 2012 #2


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    Gas is mainly empty space (unless you have a really high pressure), so the evaporation rate is nearly independent of the pressure. The condensation rate depends on the partial pressure of those molecules, therefore the equilibrium depends on the partial pressure and not the total pressure.
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