{"term":{"id":"05923","title":"standard reaction quantities","longtitle":"IUPAC Gold Book - standard reaction quantities","doi":"10.1351\/goldbook.S05923","code":"S05923","status":"current","definitions":[{"id":1,"text":"Infinitesimal changes in thermodynamic functions with extent of reaction divided by the infinitesimal increase in the extent when all the reactants and products are in their standard states. For the quantity \\(X\\) they should be denoted by \\(\\Delta _{\\rm{r}}X^{\\,\\unicode{x26ac}}\\), but usually only \\(\\Delta X^{\\,\\unicode{x26ac}}\\) is used. For specific types of reactions the subscript r is replaced by: f for formation, c for combustion, a for atomization and superscript ‡ for activation.","links":[{"term":"activation","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/A00093"},{"term":"extent of reaction","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/E02283"}],"sources":["Green Book, 2nd ed., p. 52 (https:\/\/goldbook.iupac.org\/files\/pdf\/green_book_2ed.pdf)"]}],"altoutputs":{"html":"https:\/\/goldbook.iupac.org\/terms\/view\/S05923\/html","xml":"https:\/\/goldbook.iupac.org\/terms\/view\/S05923\/xml","plain":"https:\/\/goldbook.iupac.org\/terms\/view\/S05923\/plain"},"citation":"Citation: 'standard reaction quantities' 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.S05923","license":"The IUPAC Gold Book is licensed under Creative Commons Attribution-ShareAlike CC BY-SA 4.0 International (https:\/\/creativecommons.org\/licenses\/by-sa\/4.0\/) for individual terms.","collection":"If you are interested in licensing the Gold Book for commercial use, please contact the IUPAC Executive Director at executivedirector@iupac.org .","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":"2026-07-02T17:42:37+00:00"}}