Question

A certain reaction has an activation energy of 66.0 kJ/molkJ/mol and a frequency factor of A1A1A_1 = 3.20×10¹² M−1s−1M−1s−1 . What is the rate constant, kkk, of this reaction at 27.0 ∘C∘C ?

Answer 1

Rate constant = 10.3 M^-1s^-1

Explanation

According to Arrhenius law,

rate constant, k = A * exp[-E_a / RT]

where A = frequency factor = 3.20 x 10¹² M^-1s^-1

E_a = activation energy = 66.0 kJ/mol = 66.0 x 10³ J/mol

R = constant = 8.314 J/mol-K

T = temperature = 27.0 ^oC = 300 K

Substituting the values,

k = (3.20 x 10¹² M^-1s^-1) * exp[-66.0 x 10³ J/mol / (8.314 J/mol-K * 300 K)]

k = (3.20 x 10¹² M^-1s^-1) * exp[-66.0 x 10³ J/mol / (2494.2 J/mol)]

k = (3.20 x 10¹² M^-1s^-1) * exp[-26.46]

k = (3.20 x 10¹² M^-1s^-1) * (3.22 x 10^-12)

k = 10.3 M^-1s^-1