Term: rate of conversion, \(\dot{\xi}\)
https://doi.org/10.1351/goldbook.R05147

Definition:
The rate of conversion for a reaction occurring in a closed system is defined as the time derivative of the extent of reaction: \[\overset{\text{.}}{\xi }=\frac{\mathrm{d}\xi }{\mathrm{d}t}\] In view of the definition of extent of reaction it follows that with reference to any species in a reaction showing time-independent stoichiometry \[\overset{\text{.}}{\xi }=\frac{\mathrm{d}\xi }{\mathrm{d}t}=\frac{1}{\nu _{i}}\ \frac{\mathrm{d}n_{i}}{\mathrm{d}t}\] where n i is the amount of the species at any time and ν i is its stoichiometric coefficient.

Related Terms:
1) extent of reaction (http://doi.org/10.1351/goldbook.E02283).
2) stoichiometric (http://doi.org/10.1351/goldbook.S06021).
3) coefficient (http://doi.org/10.1351/goldbook.C01124).
4) stoichiometry (http://doi.org/10.1351/goldbook.S06026).

Source: Green Book, 2nd ed., p. 55 (https://goldbook.iupac.org/files/pdf/green_book_2ed.pdf)

Citation: 'rate of conversion, \(\dot{\xi}\)' 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.R05147

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