Non-integer orders in chemical kinetics

Quimica nova

Faria, Roberto B.¹  Oliveira, André P.¹ 

[1] Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brasil

关键词: chemical kinetics;    non-integer orders;    homogeneous catalysis.;   

DOI  :  10.1590/S0100-40422010000600035

学科分类：化学（综合）

来源: Sociedade Brasileira de Quimica

【 摘 要 】

Starting from zero-,first-, and second-order integrated laws for chemical kinetics, some cases areshown which produce fractional orders. Taking the Michaelis-Menten mechanismas a first example, it is shown that substrate order can go from 1 to zero,depending on relative concentration of enzyme and substrate. Using other exampleswhich show fractional orders higher than one and even negative (inhibition),it is shown that the presence of an equilibrium before or parallel to the ratedetermining step can be the reason for fractional orders, which is an indicationof a more complex mechanism.

【 授权许可】

CC BY