Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Question about thermodynamic quantities

  1. Jun 9, 2014 #1

    kelvin490

    User Avatar
    Gold Member

    We know that for constant pressure thermodynamic processes, dH=dqp. My question is, does it implies that only reversible work is possible in this processes so that dw=0 because dv is zero? In addition, does qv necessarily be reversible heat transfer in this case? What if the heat transfer is irreversible?

    Similar question for dU=dqv, does the process need to be reversible?

    Another question is, do the above relations have anything to do with whether or not the system is an ideal gas? I have heard from a lecture that du≠dqv in Joule's free expansion for non-ideal gas. Consider reversibility and whether it's ideal gas there are four combinations of situations (ideal gas reversible,ideal gas irreversible, non-ideal gas reversible, non-ideal gas irreversible). I get confused with how these factors affect the thermodynamic relations.
     
    Last edited: Jun 10, 2014
  2. jcsd
  3. Jun 10, 2014 #2

    kelvin490

    User Avatar
    Gold Member

    Is it true that reversible process can only occur in the form of infinitesimal expansion/compression?
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Question about thermodynamic quantities
Loading...