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LPG Cylinder

  1. Feb 27, 2004 #1
    The change in pressure, caused by the release of gas from an Lpg cylinder, will cool the contents.

    i am pretty sure that it does cool the contents.

    would the water vapour condense on the surface of the bottle and freeze?
    if the gas continues to be released.
  2. jcsd
  3. Feb 28, 2004 #2


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    Ideal Gas Law: PV= NRT. If Pressure is decreased while Volume remains the same (as in a rigid metal "bottle") Temperature decreases.

    "would the water vapour condense on the surface of the bottle and freeze?"

    Yes, water vapour in the air outside bottle will form a frost on the bottle. It melts fairly rapidly once you have stopped releasing the gas. When I was young and foolish (I'm not young any more), I worked at a place that dispensed LPG. You had to be very careful not freeze your own hand!
  4. Feb 28, 2004 #3
    It is the same with CO2 fire extinguishers - if you hold the cone shaped nozzle when using it, you'll freeze your hand to it!
  5. Feb 28, 2004 #4
    alright thanx for your time and great replies
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