Term: effective molarity (effective concentration)
https://doi.org/10.1351/goldbook.E01896

Definition:
The ratio of the first-order rate constant of an intramolecular reaction involving two functional groups within the same molecular entity to the second-order rate constant of an analogous intermolecular elementary reaction. This ratio has the dimension of concentration. The term can also apply to an equilibrium constant.

Related Terms:
1) intramolecular catalysis (http://doi.org/10.1351/goldbook.I03131).
2) rate constant (http://doi.org/10.1351/goldbook.O04322).
3) intermolecular (http://doi.org/10.1351/goldbook.I03098).
4) equilibrium constant (http://doi.org/10.1351/goldbook.E02177).
5) intramolecular (http://doi.org/10.1351/goldbook.I03130).
6) molecular entity (http://doi.org/10.1351/goldbook.M03986).
7) elementary reaction (http://doi.org/10.1351/goldbook.E02035).

Source: PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1108 (https://doi.org/10.1351/pac199466051077)

Citation: 'effective molarity (effective concentration)' 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.E01896

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