https://doi.org/10.1351/goldbook.C01210
A reaction that involves more than one @[email protected] is said to occur by a @[email protected] mechanism. The terms @[email protected], @[email protected] mechanism, and @[email protected] mechanism are also commonly used. There are two main kinds of evidence for a @[email protected] mechanism: Reactions occurring in parallel, such as: Reactions occurring in forward and reverse directions are called @[email protected]: Reactions occurring in @[email protected], such as Reactions are said to exhibit feedback if a substance formed in one step affects the rate of a previous step. For example, in the scheme: @[email protected]
- The kinetic equation for the reaction does not correspond to its @[email protected]
- There is experimental evidence, direct or indirect, for intermediates of such a nature that it is necessary to conclude that more than one @[email protected] is involved.
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are called @[email protected] or @[email protected] When there are @[email protected] there is sometimes @[email protected], as in the scheme: C01210-3.png
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where B and C compete with one another for A.C01210-5.png
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are known as @[email protected]C01210-6.png
The intermediate Y may catalyse the reaction C01210-7.png (@[email protected]) or it may inhibit it (negative feedback).