Effect of Diffusion on Rate

In a homogeneous system, the rate of diffusion in the system can be directly related to the rate of the reaction as it governs the number of times the catalyst will interact with the reactants over a set time. In a biphasic system, diffusion still affects the rate of reaction, as this is dependent on the catalyst and reactants meeting. However, the rate of diffusion also affects the time it takes for the reactants to reach the place where the reaction takes place. How diffusion affects rate depends on the catalytic turnover. 

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