Imidazole is a common molecular species in biological chemistry. For example, it constitutes the side chain of the amino acid histidine. The rate constant for the protonation reaction is 5.5 × 10 10 Ms. Assuming that the reaction is diffusion controlled, estimate the diffusion coefficient of imidazole when D(H+) = 9.31 × 10-5 cm² s¹, r(H+) ~1.0 Å, and r(imidazole) = 6 Å. Use this information to predict the rate of deprotonation of imidazole by OH (D = 5.30 × 105 cm² s¹ and r = ~1.5 Å).

Imidazole is a common molecular species in biological chemistry. For example, it constitutes the side chain of the amino acid histidine. The rate constant for the protonation reaction is 5.5 × 10 10 Ms. Assuming that the reaction is diffusion controlled, estimate the diffusion coefficient of imidazole when D(H+) = 9.31 × 10-5 cm² s¹, r(H+) ~1.0 Å, and r(imidazole) = 6 Å. Use this information to predict the rate of deprotonation of imidazole by OH (D = 5.30 × 105 cm² s¹ and r = ~1.5 Å).

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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