The Arrhenius equation relates activation energy to reaction rates and temperature:
ln (k2 / k1) = (E / R) * (1/T1 - 1/T2), where E is activation energy of 272 kJ, R is the ideal gas constant (we use the units of 0.0083145 kJ/mol-K for consistency, to cancel out the kJ unit), we let T1 = 718 K and k1 = 2.30 x 10^-5, and T2 = 753 K and k2 be the unknown.
ln (k2 / 2.30x10^-5) = (272 kJ / 0.0083145 kJ/mol-K) * (1/718 - 1/753)
k2 = 1.91 x 10^-4 /s
