Reaction Rates Problem

Question

The reaction C4H8 (g) -> 2C2H4 (g) has an activation energy of 262KJ/mol. At 600K, the rate constant, k,  is 6.1x10^-8s-1. What is the value of the rate constant at 805K?

Answer 1

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

NOTE: Since R has units of J/K-mole, we will change Ea to 262,000 J/mole

k1 = 6.1x10^-8 s^-1

T1 = 600K

k2 = ?

T2 = 805K

R = 8.314 J/mol-K

ln (6.1x10^-8/k2) = 262,000/8.314 (1/805 - 1/600)

10.08 - ln k2 = 31513 (0.00124 - 0.00167)

10.08 - ln k2 = 39.08 - 52.63

-ln k2 = -23.63

k2 = 7.7x10^-8 s^-1

(assuming the math is correct)