1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Internal energy of a gas

  1. May 19, 2008 #1
    [SOLVED] Internal energy of a gas

    Is the internal energy of a gas simply the total kinetic energy possesed by the particles? I ask this, since I have read this to be the case, however I have also read that when changing state, eg. from liquid to gas, the latent heat is the energy required to increase the potential enrgy of the particles, as well as do work against external pressure. If energy is put in to increase the potential energy, surely some of the internal energy of the gas is potential energy, as well as kinetic energy, isn't it?

    Thanks
     
  2. jcsd
  3. May 19, 2008 #2

    Hootenanny

    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    You are indeed correct. The internal energy of a gas can be thought of as the sum of the kinetic and potential energies of the constituent molecules. However, note that for the special case of an ideal gas, it is assumed that the molecules do not interact, i.e. there is no potential energy. Hence, for an ideal gas the internal energy is the kinetic energy of the molecules, since there is no potential component.

    Further reading: Internal Energy @ Hyperphysics

    I hope that makes sense.
     
  4. May 19, 2008 #3
    Thank you ever so much, it makes alot more sense now!
     
  5. May 19, 2008 #4

    Hootenanny

    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    A pleasure :smile:

    Don't forget to mark this thread a 'solved' when your done, thanks.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Internal energy of a gas
Loading...