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Would Co2 be liquid or gas?

  1. Oct 6, 2014 #1
    Let's say you have a 20 bar atmosphere of 95% nitrogen, 3% oxygen, 1% argon and 1% Co2 cooled to 0 F. Would Co2 be liquid or gas?
  2. jcsd
  3. Oct 6, 2014 #2


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    Get yourself a CO2 phase diagram and see.
  4. Oct 6, 2014 #3
    The partial pressure is 0.2 bar so it would be gas. However with the whole atmosphere is would be liquid.
  5. Oct 6, 2014 #4
    The vapor pressure of co2 at 0F is about 20 bars, and the partial pressure of the co2 in your gas mixture is about 1 bar. So it won't condense.

  6. Oct 7, 2014 #5
    Here's where I'm confused is it the partial pressure of Co2 that determines which state its in or the total atmosphere? Because if in this scenario the temperature were -40 F Co2 would be liquid with the total atmosphere but it would be gas at partial pressure.
  7. Oct 7, 2014 #6
    It's the partial pressure that matters, not the total pressure.

  8. Oct 7, 2014 #7


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    Which would you think it should be? It is nice to be told a confirmation, but it is not that much help to you really if you can't or don't reason it out mechanistically.
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