The general defination of the activation energy `E_(a)` of any rate process, applicable whether or not `E_(a)` varies with T, is:
`E_(a)=RT^(2).(d(l n k))/(dT)`
For a first order reaction, the dependence of rate constant on temperature is given as:
`l n k[//s^(-1)]=27.72-(2.0xx10^(4))/(T[//K]`
The activation energy of reaction at 300 K is:

Options

A. `166.28 kcal//mol`
B. `80.0kcal//mol`
C. `40.0 k cal//mol`
D. `20.9 kcal//mol`

Answer

C