Like the
rate of consumption,
the rate of formation of a specified product may be defined in two ways:
-
As the time derivative of the amount of a product. Thus for a product Y, present at
any time in amount
.
the rate of its formation may be given by:
This definition is particularly appropriate for open systems.
-
For kinetics in closed systems it is more usual to define a rate of formation per
unit volume, denoted
:
When the volume is constant this reduces to:
When the volume is not constant the relationship
may be differentiated to give:
and the rate of formation becomes:
A rate of formation may be specified even for a reaction of time dependent stoichiometry or of unknown stoichiometry.
Source:
PAC, 1996, 68, 149
(A glossary of terms used in chemical kinetics, including reaction dynamics (IUPAC
Recommendations 1996))
on page 181
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.
https://doi.org/10.1351/goldbook.
in flame emission and absorption spectrometry
or
