Temperature Dependence of Rate Constants

Rate constants, like equilibrium constants, are temperature-dependent. Unlike K, however, k virtually always increases with increasing temperature. The temperature-dependence usually obeys the Arrhenius equation,

            (1.1)

where A is called the frequency factor and Ea is the activation energy. The logarithmic form of the Arrhenius equation,

the same form as eq (1.2) for In K, with Ea replacing DH° and In A replacing DS°/R.

           (1.2)

Comparing rate constants measured at two different temperatures, we can derive the analog of Eq. (1.2):

         (1.3)