In your laboratory you\'re studying a chemical reaction that follows the general
ID: 739725 • Letter: I
Question
In your laboratory you're studying a chemical reaction that follows the general rate law: rate = k[A]2. Initial experiments show a rate of 0.0009784 M/s when [A] = 0.871 M at 279 K. You add a catalyst to the reaction, which is known to change the activation energy of the process by 4.3 kJ. What will the rate of the reaction be with the catalyst when [A] = 0.0547 M at 323 K? Assume that the Arrhenius factor for this reaction has been determined to be 0.729 M-1s-1.No units are required for this problem answer
Explanation / Answer
K = rate/[A]2 = 0.0009784 / 0.871^2 = 1.29* 10^-3 K = A exp(-Ea / RT) => 1.29* 10^-3 = 0.729 * exp(-Ea / 8.314 *279) => Ea = 14700 J Ea2 = 14700 - 4300 = 10400.4 J K2 = A exp(-Ea/RT) => K2 = 0.729 * exp(-10400.4 / 8.314*323) => K2 = 0.0152 => rate = K2[A]2 = 0.0152 * 0.0547^2 = 4.537 * 10^-5 M/s