The @P04420@ (fugacity) of a solute (B) in a solution is directly proportional to the rational chemical activity (\(a_{x}\)) of the solute; this relationship is called @H02782@'s law: \[p_{\text{B}}=\frac{a_{x,\text{B}}}{\alpha _{x,\text{B}}^{\infty }}\] where \(\alpha _{x,\text{B}}^{\infty }\) is the rational @S05740@ @C01124@ for infinite dilution, i.e. for pure solvent. For the solvent (A) the relationship is called @R05135@, and the proportionality factor is the fugacity of the pure solvent, \(\overset{˜}{p}_{\text{A}}^{\ast }\): \[p_{\text{A}}=\overset{˜}{p}_{\text{A}}^{\ast }\ a_{\text{A}}\]
PAC, 1984, 56, 567. (Physicochemical quantities and units in clinical chemistry with special emphasis on activities and activity coefficients (Recommendations 1983)) on page 571 [Terms] [Paper]
See also:
PAC, 1990, 62, 2167. (Glossary of atmospheric chemistry terms (Recommendations 1990)) on page 2193 [Terms] [Paper]
PAC, 1994, 66, 533. (Standard quantities in chemical thermodynamics. Fugacities, activities and equilibrium constants for pure and mixed phases (IUPAC Recommendations 1994)) on page 544 [Terms] [Paper]