kinetic activity factor

A factor involving activity coefficients that appears as a multiplier in the rate equation. For a bimolecular reaction the factor is

$y A y B y ‡$ ,

where $y A$ , $y B$ and $y ‡$ are the activity coefficients for the reactants A and B and the activated complex, respectively. For a unimolecular reaction the factor is

$y A y ‡$ ,

and for a trimolecular reaction it is

$y A y B y C y ‡$ .

Source:

PAC, 1996, 68, 149 (A glossary of terms used in chemical kinetics, including reaction dynamics (IUPAC Recommendations 1996)) on page 171