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Entropy, energy, equilibrium

  1. Mar 18, 2010 #1
    I've been thinking about some relations between energy, entropy and equilibrium but I don't know if I'm right.

    We know that everything in nature tends to the equilibrium, right? Also in every system in universe the entropy tends to increase... so, the higher the entropy the higher is the equilibrium is the system, that's right?

    I also thought that mechanical work is the way that the potential energy is converted into kinetic energy. Potential energy means disequilibrium, because if something has potential energy that means that this thing has energy stored in some place, and this energy is certainly going to be converted into kinetic energy in some moment (so it will generate disequilibrium because we will have a force, because work is force times distance).

    If my thinks are right I can conclude that everything tends to equilibrium, the entropy tends to increase and the potential energy tends to decrease in every system.

    Am I right? or am I just saying absurds?

    Thanks all
  2. jcsd
  3. Mar 18, 2010 #2


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    Yes, in general, energy tends to decrease and entropy tends to increase as you go towards equilibrium, this is usually taught in HS chemistry.

    Enthalpy (energy) wants to go down, Entropy wants to go up.
  4. Mar 19, 2010 #3
    I wouldn't say it this way. It's rather that nature stay in stable states, because... they are stable. So it evolves randomly, but once it reaches a states that has himself as the successor, it will stay there forever for obvious reasons.

    For this I started another thread
    Entropy doesn't have to increase. It is just very very likely that it will, if there are very many particles. Occationally entropy can drastically decrease.

    I think this isn't true in general. This idea might only work if you add some more contraints. Maybe considering gases only? Or other special systems? Not sure...
    Anyone a suggestion? I find that interesting. A suppose a good starting point is
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