What is the activation energy Ea for a reaction that has a rate constant of 0.245s−1 at a temperature of 273K and a rate constant of 0.518s−1 at a temperature of 315K ?

Question

What is the activation energy Ea for a reaction that has a rate constant of 0.245s−1 at a temperature of 273K and a rate constant of 0.518s−1 at a temperature of 315K ?

Answer 1

Check out an extension of the Arrhenius equation:

ln (k1/k2) = Ea/R (1/T2 - 1/T1)

k1 = 0.245 s^-1

T1 = 273K

k2 = 0.518 s^-1

T2 = 315K

R = 8.314 J/Kmole

Ea = ?

ln(0.245/0.518) = Ea/8.314 (1/315 - 1/273)

-0.7487 = Ea/8.314 (0.003175 - 0.003663)

-0.7487 = Ea/8.314 (-0.0004880)

Ea = 1.28x10⁴ J/mole

(Please check my math)