The Arrhenius law

The Arrhenius law gives the dependence of the equilibrium constant on temperature. \begin{equation} k=Ae^{-E_a/RT} \end{equation} A is the frequency factor, related to the frequency with which the activated complex decomposes into products.

Where:

• $k$ is the reaction rate constant,
• $A$ is the pre-exponential factor or frequency factor,
• Ea​ is the activation energy of the reaction,
• $R$ is the ideal gas constant, and
• $T$ is the temperature in kelvins.

The Arrhenius Law equation shows how the reaction rate constant ($k$) varies exponentially with temperature. An increase in temperature leads to a significant increase in the reaction rate.

$E_a$ represents the activation energy of the reaction, which is the energy difference between the reactants and the transition state. The use of catalysts allows lowering this energy, increasing the reaction rate. Combining the Arrhenius Law at two temperatures gives us the equation that allows us to calculate the kinetic constant at one temperature, provided we know its value at another temperature and the activation energy of the reaction. \begin{equation} \ln\frac{k_2}{k_1}=\frac{-Ea}{R}\left(\frac{1}{T_2}-\frac{1}{T_1}\right) \end{equation}