Activation energy equation

Arrhenius Equation:

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VarshiniC
Posts: 31
Joined: Mon Jan 09, 2023 9:51 am

Activation energy equation

Postby VarshiniC » Mon Mar 20, 2023 4:17 pm

How is this equation derived from the given equations on the equation list?

k'/k=Ea/R(1/T1-1/T2)

yushensun 3F
Posts: 34
Joined: Mon Jan 09, 2023 9:32 am

Re: Activation energy equation

Postby yushensun 3F » Mon Mar 20, 2023 4:34 pm

Do you mean this one?
Image
I'm not sure about the one you asked but there's this one

Levy Shaked
Posts: 79
Joined: Fri Sep 29, 2023 12:04 pm

Re: Activation energy equation

Postby Levy Shaked » Sat Mar 02, 2024 4:11 pm

For a reaction at a particular temperature, ln(k) = lnA -(Ea/R)(1/T), where Ea represents the activation energy of a reaction and A is correlated with collision frequency of reactants. Compared to the proportion of collisions with sufficient energy to overcome Ea, collision frequency changes little with respect to temperature, and so A is assumed to be relatively constant across temperature changes.

Constant values of A can be taken advantage of by rearranging the above equation to be lnA = ln(k) + (Ea/R)(1/T) at any temperature. Thus, for two temperatures T1 and T2, ln(k1) + (Ea/R)(1/T1) = lnA = ln(k2) + (Ea/R)(1/T2). This equation can then be arranged into the form

ln(k2/k1) = -(Ea/R)(1/T2 - 1/T1).


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