Term: rate of consumption, \(\nu_{n\text{,B}}\), \(\nu_{c\text{,B}}\)
https://doi.org/10.1351/goldbook.R05146

Definition:
As the negative of the time derivative of the amount of reactant; thus for a reactant B, present at any time in amount nB, the rate of its consumption may be defined as: \[\nu (n_{\text{B}}) = -\frac{\text{d}n_{\text{B}}}{\text{d}t}\] This definition is particularly appropriate for open systems. Here and elsewhere, when a rate is defined in terms of a time derivative, it must be understood that the definition relates to the process occurring in isolation. In a flow system there may be no actual changes with time, and the time derivative must be inferred. Such an inference is also required for a reaction occurring by a composite mechanism.

Related Terms:
1) composite mechanism (http://doi.org/10.1351/goldbook.C01210).

Source: 

Citation: 'rate of consumption, \(\nu_{n\text{,B}}\), \(\nu_{c\text{,B}}\)' 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.R05146

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