Title: composite reaction
Long Title: IUPAC Gold Book - composite reaction
DOI: 10.1351/goldbook.C01211
Status: current

Definition
A chemical reaction for which the expression for the rate of disappearance of a reactant (or rate of appearance of a product) involves rate constants of more than a single elementary reaction. Examples are 'opposing reactions' (where rate constants of two opposed chemical reactions are involved), 'parallel reactions' (for which the rate of disappearance of any reactant is governed by the rate constants relating to several simultaneous reactions to form different respective products from a single set of reactants), and stepwise reactions.

Related Terms
- chemical reaction: https://goldbook.iupac.org//terms/view/C01033
- elementary reaction: https://goldbook.iupac.org//terms/view/E02035
- opposing reactions: https://goldbook.iupac.org//terms/view/O04302
- rate of appearance: https://goldbook.iupac.org//terms/view/R05156
- rate of disappearance: https://goldbook.iupac.org//terms/view/R05148
- simultaneous reactions: https://goldbook.iupac.org//terms/view/S05680
- stepwise reactions: https://goldbook.iupac.org//terms/view/S05970

Sources
- PAC, 1993, 65, 2291. 'Nomenclature of kinetic methods of analysis (IUPAC Recommendations 1993)' on page 2293 (https://doi.org/10.1351/pac199365102291)
- PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1098 (https://doi.org/10.1351/pac199466051077)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/C01211/html
- json: https://goldbook.iupac.org/terms/view/C01211/json
- xml: https://goldbook.iupac.org/terms/view/C01211/xml

Citation: Citation: 'composite reaction' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351/goldbook.C01211
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Accessed: 2026-04-20T18:50:18+00:00