https://doi.org/10.1351/goldbook.S06178
The function relating, at constant temperature and pressure, , or , or the respective specific quantities , or to the in the equilibrium liquid phase. With solutions of more than two components such isotherms are unequivocal functions only when the ratios of the are kept constant. ( is the , , are relative adsorptions, is the change in resulting from bringing a specified mass of solid into contact with a specified amount of solution , is the change in concentration resulting from bringing a specified mass of solid into contact with a specified amount of solution of volume .)
mole fraction
(or concentration) of component mole
fractions (or concentrations) of all other components except area of interface
, mole fraction
of