Title: reaction step
Long Title: IUPAC Gold Book - reaction step
DOI: 10.1351/goldbook.R05178
Status: current

Definition
An elementary reaction, constituting one of the stages of a stepwise reaction in which a reaction intermediate (or, for the first step, the reactants) is converted into the next reaction intermediate (or, for the last step, the products) in the sequence of intermediates between reactants and products.

Related Terms
- elementary reaction: https://goldbook.iupac.org/terms/view/E02035
- rate-limiting step: https://goldbook.iupac.org/terms/view/R05140
- reaction intermediate: https://goldbook.iupac.org/terms/view/R05171
- reaction stage: https://goldbook.iupac.org/terms/view/R05177
- sequence: https://goldbook.iupac.org/terms/view/ST06775
- stepwise reaction: https://goldbook.iupac.org/terms/view/S05970

Source
- PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1159 (https://doi.org/10.1351/pac199466051077)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/R05178/html
- json: https://goldbook.iupac.org/terms/view/R05178/json
- xml: https://goldbook.iupac.org/terms/view/R05178/xml

Citation: Citation: 'reaction step' 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.R05178
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Disclaimer: The International Union of Pure and Applied Chemistry (IUPAC) is continuously reviewing and, where needed, updating terms in the Compendium of Chemical Terminology (the IUPAC Gold Book). Users of these terms are encouraged to include the version of a term with its use and to check regularly for updates to term definitions that you are using.
Accessed: 2026-06-14T16:49:31+00:00