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Exponent value in Arrhenius Equation

  1. May 20, 2012 #1
    This may be a pretty dumb question, but how is it that as the exponent value of e decreases, the rate k increases? This seems counter-intuitive, and when I enter values for e into my calculator and compare them, the higher exponents (e.g. 50 vs. 20) give higher results.
  2. jcsd
  3. May 20, 2012 #2
    The Arrhenius equation is

    k = A*e-Ea/RT

    where k is the rate constant, A is the pre-exponential factor, Ea is the activation energy, R is the gas constant, and T is the temperature (in Kelvin). What are you changing to get the exponential factor to change?

    ETA - Also, don't forget the properties of exponents. For the real numbers a and b , where a ≠ 0, one has a-b = 1/ab.

    Hopefully it's becoming a bit more clear with those reminders!
    Last edited: May 20, 2012
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