Term: rate of formation, \(\nu _{n\text{,y}}\), \(\nu_{\text{c,y}}\)
https://doi.org/10.1351/goldbook.R05152

Definition:
As the time derivative of the amount of a product. Thus for a product Y, present at any time in amount nY. the rate of its formation may be given by: \[\nu (n_{\text{Y}}) = \frac{\text{d}n_{\text{Y}}}{\text{d}t}\] This definition is particularly appropriate for open systems.

Source: 

Citation: 'rate of formation, \(\nu _{n\text{,y}}\), \(\nu_{\text{c,y}}\)' 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.R05152

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