Questions about the Arrhenius equation

This post was last edited by qugd on 2012-12-19 at 13:44. It is best to express the issue using specific data and formulas. Such vague questions cannot be accurately understood or answered. There are several ways to express this formula; the indefinite integral form does not impose any restrictions on the temperature range, which means that the activation energy is also a function of temperature as well – it is a general form of the formula. If the temperature is near absolute zero, or even approaches the temperature of a nuclear explosion, it’s indeed difficult to discuss such matters, as our knowledge of physical chemistry is too limited. However, for differential and definite integral forms, since the assumed activation energy remains constant within a certain temperature range, its specific meaning certainly refers to this particular temperature range; yet this range is determined based on the specific chemical reaction and the specific conditions. When analyzing the thermodynamics and kinetics of analytical chemistry, it is necessary to take practical circumstances into account; theoretical formulas merely provide a basic conceptual representation. Without specific details regarding chemical reactions and their conditions, such discussions can be considered metaphysical.

The assumption underlying the Arrhenius equation is that the activation energy Ea is considered a constant independent of temperature; therefore, it can only match experimental results within a certain temperature range. This temperature range is generally the one corresponding to the experimental data used for fitting the activation energy and pre-exponential factor.