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Calculating Ea through slope

  1. Feb 13, 2005 #1
    For some reason, this isnt working out.

    The Arhennius equation, k = A*e^(-Ea/RT)

    I have tables of temperature and k. The book says just calculate it by having the x axis be 1/T and y axis be ln(k)

    Ok, take Ln of both sides
    ln(k) = ln(A*e^(-Ea/RT))
    ln(k) = -Ea/RT + ln(A)

    Oh, that looks like y = mx + b
     
  2. jcsd
  3. Feb 13, 2005 #2

    dextercioby

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    So there's actually no problem.It's a standard way of linearizing exponential laws...

    Daniel.
     
  4. Feb 13, 2005 #3
    Ya, I was just being stupid.
     
  5. Feb 13, 2005 #4

    Gokul43201

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    Note that Ea will be the absolute value of the slope. The slope will be negative, Ea must be positive.
     
  6. Feb 13, 2005 #5

    dextercioby

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    Gokul,if you wanted to be strict,u should have mentioned that Ea is the absolute value of the slope TIMES THE GAS CONSTANT "R"...

    Daniel.
     
  7. Feb 13, 2005 #6

    Gokul43201

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    I should have.

    It's common to make the x-axis 1/RT or [itex]\beta[/itex] (when dealing with numbers instead of moles).
     
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