The rate constant,

CHEMISTRY · Multi-part · A Level · Chemistry · Kinetics · Kinetics

Problem

The rate constant, kk, was determined for a reaction at various temperatures. The results are given in the table.
Temperature / °CSecond-order rate constant, k/mol−1dm3s−1k / \text{mol}^{-1} \text{dm}^3 \text{s}^{-1}
56.81×10−66.81 \times 10^{-6}
151.40×10−51.40 \times 10^{-5}
252.93×10−52.93 \times 10^{-5}
356.11×10−56.11 \times 10^{-5}
(1) Plot a graph of ln⁡k\ln k against T−1T^{-1} where TT must be expressed as an absolute temperature. (Plot the ln⁡k\ln k axis from −12-12 to −8-8 and the T−1T^{-1} axis from 0.00300.0030 to 0.00380.0038 .) (2) Calculate the gradient of your Arrhenius plot and use it to determine a value for the activation energy, EaE_a , in kJ mol−1\text{kJ mol}^{-1} . (3) Calculate an approximate value for the Arrhenius constant, AA , using the Arrhenius plot.

Related theory

Browse the problem library