The increment of the value of a quantity
with time.
The change may be expressed either infinitesimally at time
by the differential
or
,
or in practice it may be expressed by a finite increment over the
time interval
, i.e.
, which may be written
or
Examples are: mass change,
;
amount of substance change,
; volume change,
;
substance concentration change,
.
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.
