A chemical reaction has an energy of activation Ea = 1∙104 J mol-1 at T = 300 K. The first-order rate constant for this reaction was found to be 15.0 s-1. In the presence of a catalyst, the activation energy is reduced to 1∙103 J mol-1. Calculate the pre-exponential factor in the Arrhenius equation

Answer : The pre-exponential factor in the Arrhenius equation is, 14.99  s⁻¹

Explanation :

Using Arrhenius equation,

Taking ln on both the sides, we get:

where,

K = rate constant =

Ea = activation energy = 1.104 J/mol

T = temperature = 300 K

R = gas constant = 8.314 J/mole.K

A = Arrhenius constant

Now put all the given values in the above formula, we get the value of \ln a.

Therefore, the pre-exponential factor in the Arrhenius equation is, 14.99  s⁻¹