Activation energy of a chemical reaction can b determined by :

By utilising the Arrhenius equation to calculate the rate constants at two temperatures, it is possible to calculate the activation energy of a chemical reaction.
The temperature dependence of reaction rates is given by the Arrhenius equation.

${\log }_{10}\frac{{\mathrm{k}}^{\mathrm{\prime }}}{\mathrm{k}}=\frac{{\mathrm{E}}_{\mathrm{a}}}{2.303\mathrm{R}}\left[\frac{{\mathrm{T}}^{\mathrm{\prime }}-\mathrm{T}}{{\mathrm{TT}}^{\mathrm{\prime }}}\right]$.