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

Homework Help: Kinetic Theory

  1. Apr 21, 2006 #1
    Hi

    I wanted to know : -

    Most gases increase in temperature when they are compressed . Where does the energy for this come from .

    When a change of state from liquid to gases occurs is it accompanied by change in the internal energy of the liquid molecules ?

    Thanks a lot ..
     
  2. jcsd
  3. Apr 21, 2006 #2

    Hootenanny

    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    Using the first law of thermodynamics; [itex]\Delta U = Q - W[/itex], [itex]W[/itex] is defined as the work done by the system. Now, when you compress a gas you have to apply a force and since work done is the intergral of force, when you compress a gas you are doing work on the gas. Therefore, you are inceasing the internal energy of the gas and hence the temperature increases.

    ~H
     
  4. Apr 21, 2006 #3
    When a change of state from liquid to gases occurs is it accompanied by change in the internal energy of the liquid molecules ?
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook