measurement datum reaction rate http://purl.obolibrary.org/obo/STATO_0000071 reaction rate is a measurement datum which represents the speed of a chemical reaction turning reactive species into product species of event (i.e the number of such conversions)s occuring over a time interval Term IRI: http://purl.obolibrary.org/obo/PATO_0000161 Definition: A quality of a single process inhering in a bearer by virtue of the bearer's occurrence per unit time. [database_cross_reference: PATOC:melissa] [Wikipedia] A measurement datum about the speed at which a chemical reaction takes place, defined as proportional to the increase in the concentration of a product per unit time and to the decrease in the concentration of a reactant per unit time.