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Doubts regarding heat pump

  1. Sep 23, 2011 #1
    let's say some amount of heat is absorbed by a refrigerant for phase change at a low pressure. will this heat absorbed be equal to the heat given out by the compressed refrigerant at high pressure?
    i know that the amount of heat required for phase change from liquid to vapour is less at low pressure.
    similarly does the amount of heat required for condensation depend on how much pressure is being applied?
    as far as i understand the heat pump functions using the latent heat(of phase change) property of the refrigerant to absorb and reject more heat at small temperature differences. so that more heat flows as the temperature doesnt change during the phase change. am i right?
    and please answer the above two questions too. :) and in layman's terms.. :P
  2. jcsd
  3. Sep 23, 2011 #2
    it's about the same. latent heat is a molecular matter, and pressure has an effect but very small in most cases.

    latent enthlapy, however, depends on pressure yes. For substances where the volume changes significantly (during phase change) and the latent heat is low, pressure has a greater role.
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