Title: reaction probability
Long Title: IUPAC Gold Book - reaction probability
DOI: 10.1351/goldbook.R05176
Status: current

Definition
The probability that a reaction occurs when two particles undergo a collision. If \(N_{\rm{c}}\) is the number of collisions occurring in unit time, and \(N_{\rm{r}}\) the number of reactions occurring in unit time: \(P_{\rm{r}}=\frac{N_{\rm{r}}}{N_{\rm{c}}}\).

Related Term
- probability: https://goldbook.iupac.org//terms/view/P04855

Source
- PAC, 1996, 68, 149. 'A glossary of terms used in chemical kinetics, including reaction dynamics (IUPAC Recommendations 1996)' on page 184 (https://doi.org/10.1351/pac199668010149)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/R05176/html
- json: https://goldbook.iupac.org/terms/view/R05176/json
- xml: https://goldbook.iupac.org/terms/view/R05176/xml

Citation: Citation: 'reaction probability' 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.R05176
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Accessed: 2026-06-20T06:03:10+00:00