The temperature dependence of the reaction rate is usually expressed as follows: k = k. rt where k is the reaction rate constant; ko is a pre-exponential constant, e is the activation energy, r is the universal gas constant and t is the absolute temperature. however, the following expression is used for the bod (biochemical oxygen demand) test: kt, = kt, (o)(t3-t; ) a) show that a = ert, i and thus 0 is a function of t, and t2 b) determine the activation energy, e, if e = 1.047 and t2 =293 k and t = 273k