Correlation between activation energy and reaction temperature as observed in thermal analysis kinetics

The activation energies (E) and temperatures (T) of a variety of chemical reactions are analyzed to reveal the following correlation: E(kJ/mol)=(35±12)+(0.46±0.04)T(°C). The correlation is statistically significant having the Pearson's coefficient of linear correlation 0.873. Consequently, 76 % of the observed variation in the activations energy is caused by the actual relationship between E and T, whereas only 24 % is attributed to chance. A statistically similar correlation is revealed for crystallization of glasses. In practice, such correlations can be used to estimate the initial E values in nonlinear optimization of kinetic models or to quickly check whether the experimental activation energies disagree excessively with the expected values. An attempt is made to identify the physical origins of the correlation.