Determine the activation energy for the reaction. Please help... exam tomorrow!?

Question

The Arrhenius equation can be used to determine the rate constant at a different temperature.

For the following reaction H2 + I2 ==> 2HI, the rate constant at two different temperatures was determined:

Temperature(K): ________ Rate Constant (M^-1 s-1):

400 ____________ 0.0234
500 ____________ 0.750

Determine the activation energy for the reaction...


Thank you in advanced! Will help a lot for my test tomorrow.

Answer 1

ln (k2/k1) = (Ea/R) * (1/T1 - 1/T2)
Ea = R ln (k2/k1) / (1/T1 - 1/T2)
Ea = 8.314 * ln (0.750 / 0.0234) / (1/400 - 1/500)
Ea = 8.314 * 3.467 / 0.0005
Ea = 57650 J = 57.7 kJ