activity (relative activity), Math - title
Defined by the equation
Math - e
where Math - text is the gas constant, Math - text the thermodynamic temperature, Math - text the chemical potential and Math - text the standard chemical potential the definition of which depends on the choice of the standard state.
See also: absolute activity
Green Book, p. 49
PAC, 1996, 68, 957 (Glossary of terms in quantities and units in Clinical Chemistry (IUPAC-IFCC Recommendations 1996)) on page 989