Term: mixing control
https://doi.org/10.1351/goldbook.M03946

Definition:
The experimental limitation of the rate of reaction in solution by the rate of mixing of solutions of the two reactants. It can occur even when the reaction rate constant is several powers of 10 less than that for an encounter-controlled rate. Analogous (and even more important) effects of the limitation of reaction rates by the speed of mixing are encountered in heterogeneous (solid/liquid, solid/gas, liquid/gas) systems.

Related Terms:
1) microscopic diffusion control (http://doi.org/10.1351/goldbook.M03912).
2) stopped flow (http://doi.org/10.1351/goldbook.S06033).
3) rate of reaction (http://doi.org/10.1351/goldbook.R05156).
4) encounter-controlled (http://doi.org/10.1351/goldbook.E02089).
5) rate constant (http://doi.org/10.1351/goldbook.O04322).

Source: PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1141 (https://doi.org/10.1351/pac199466051077)

Citation: 'mixing control' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.M03946

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