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Eyring polanyi vs arrhenius equation

  1. Dec 2, 2012 #1
    They both are derived from same kinetic theory of gases, but I've heard that eyring polanyi equation is more advantageous over the arrhenius equation. Why do you think that is the case?
     
  2. jcsd
  3. Dec 3, 2012 #2

    DrDu

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    Arrhenius equation is purely empirical, while the Eyring Polanyi equation is derived from the microscopic mechanism.
     
  4. Dec 3, 2012 #3
    According to a brief examination of the varaibles and constants involved in the arrenhenius equation and eyring polanyi equation, what I've noticed is that there are more parameters of the transition state (such as entropy and enthalpy) involved in the eyring polanyi equation as opposed to only just the activation energy that can be determined from the arrenhrnius one, and also the preexponential factor in the arrenhenius equation doesnt really tell us much..
    Am I on the right track?
     
  5. Dec 4, 2012 #4

    DrDu

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    When you logarithmize both equations, you will get a linear equation in case of the Arrhenius plot. In the case of the EP equation, the relation will be slightly nonlinear.
    You can find the best Arrhenius like approximation to the EP equation from the slope and offset of the line tangent to the logarithmized EP equation at a given point.
    Try to determine the values of the Arrhenius prefactor and energy this way!
     
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