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The desire of atoms for a lower energy state

  1. Jan 31, 2010 #1
    Could anybody explain to me why it is that atoms desire (sorry about the personification) a lower energy state? It just occured to me as I was studying enthalpy changes at school...
  2. jcsd
  3. Jan 31, 2010 #2


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    Hi Tready2, welcome to PF. Yes, let's not anthropomorphize our particles (they don't like it :smile:)

    Systems tend to fall into the lowest energy state because any energy emitted quickly dissipates as thermal energy and is lost. In a similar way, it's totally unremarkable for a ball to fall off a table and for the resulting sound, vibrations, and frictional heat to dissipate, but it would be incredibly unlikely for random noise and heat to accumulate to make the same ball leap up to the table again.

    This general principle is what the Second Law of Thermodynamics is all about: there's a tendency for a system to relax into the lowest possible energy configuration, and this tendency increases with system size.

    Does this answer your question?
  4. Jan 31, 2010 #3
    Can an example of the second law of thermodynamics be that a system is constantly going from order to disorder? Of course that is in the physical realm, not the thermal one.
  5. Jan 31, 2010 #4
    Everything in nature just likes to occupy the lowest energy possible.
    It's called the principle of minimum energy, and is another way to rephrase the 2nd law of thermodynamics.

    Why it happens, no one knows. Nature is just lazy! :)
  6. Jan 31, 2010 #5
    I just noticed that the second law of thermodynamics describes me very well!
  7. Apr 7, 2010 #6
    Yes. It helped alot :) Thank you!
    P.s. Sorry I didn't reply for ages!
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