Term: rate law (empirical differential rate equation)
https://doi.org/10.1351/goldbook.R05141

Definition:
An expression for the rate of reaction of a particular reaction in terms of concentrations of chemical species and constant parameters (normally rate coefficients and partial orders of reaction) only. For examples of rate laws see equations (1)-(3) under kinetic equivalence, and (1) under steady state.

Related Terms:
1) rate of reaction (http://doi.org/10.1351/goldbook.R05156).
2) chemical species (http://doi.org/10.1351/goldbook.CT01038).
3) rate coefficients (http://doi.org/10.1351/goldbook.R05137).
4) orders of reaction (http://doi.org/10.1351/goldbook.O04322).
5) kinetic equivalence (http://doi.org/10.1351/goldbook.K03403).
6) steady state (http://doi.org/10.1351/goldbook.S05962).

Source: PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1157 (https://doi.org/10.1351/pac199466051077)

Citation: 'rate law (empirical differential rate equation)' 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.R05141

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