A term which may be expressed infinitesimally at time
by a ratio of differentials
where the kind of quantities are the same but for different components in the same system. In practice, the ratio for a finite interval is:
Examples are: mass change ratio,
;
amount of substance change ratio,
.
Source:
PAC, 1992, 64, 1569
(Quantities and units for metabolic processes as a function of time (IUPAC Recommendations 1992))
on page 1571
Cite as:
IUPAC. Compendium of Chemical Terminology, 2nd ed. (the "Gold Book"). Compiled by A. D. McNaught and A.Wilkinson. Blackwell Scientific Publications, Oxford (1997). XML on-line corrected version: http://goldbook.iupac.org (2006-) created by M. Nic, J. Jirat, B. Kosata; updates compiled by A. Jenkins. ISBN 0-9678550-9-8.
doi:10.1351/goldbook.
