Term: chain branching
https://doi.org/10.1351/goldbook.C00948

Definition:
When in a chain reaction there is a net increase in the number of chain carriers there is said to be chain branching. A simple example of a chain-propagating reaction leading to chain branching is: C00948.png in which there is one chain carriers (an oxygen atom) on the left and two chain carriers (a hydrogen atom and a hydroxyl radical) on the right.

Related Terms:
1) degenerate chain branching (http://doi.org/10.1351/goldbook.D01557).
2) chain reaction (http://doi.org/10.1351/goldbook.C00960).
3) chain carrier (http://doi.org/10.1351/goldbook.C00949).
4) chain-propagating reaction (http://doi.org/10.1351/goldbook.C00959).

Image: Not defined (https://goldbook.iupac.org/img/inline/C00948.png) 

Source: PAC, 1996, 68, 149. 'A glossary of terms used in chemical kinetics, including reaction dynamics (IUPAC Recommendations 1996)' on page 156 (https://doi.org/10.1351/pac199668010149)

Citation: 'chain branching' 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.C00948

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