Activation Energy: Dependence Explained

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    Activation Energy
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Activation energy (Ea) is generally considered to be independent of temperature, despite its apparent dependence in the Arrhenius equation. The equation can be rearranged to show that while the rate constant (k) changes with temperature, the activation energy remains constant. This is supported by classical chemistry experiments where plotting ln(k) against 1/T yields a straight line, allowing for the calculation of Ea using the slope, which is equal to Ea/R. Thus, while k varies with temperature, Ea does not.
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Is activation energy dependent?

I think it isn't, but if you rearrange the Arrhenius equation you get:
Ea - activation energy
Ea = RT(lnA - lnk)
so as temperature Ea can change. But I am thinking that k will also change in relation so Ea is constant?
 
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Ea is temp. independent, K will change with a change in T. So if T changes the -lnK factor will change so Ea will always be constant. A classical chemistry experiment at universities is plotting lnK vs. 1/T. The rate of the reaction at different temperatures is recorded in the lab. From the straight line in plot of lnk vs 1/T you can calculate the slope and the slope is equal to Ea/R.
 
ok thanks very much.
 

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