A dispersion parameter and an induction parameter are used to estimate this quantity in the MOSCED model. Both the NRTL and Wilson model of this quantity cannot describe its extrema, unlike a two-suffix model named after this quantity that takes a power series of Gibbs free energy over RT with respect to mole fraction and is named after Max Margules. This quantity is divided into residual and combinatorial (15[1])components in the (*) UNIFAC model. The Pitzer equation gives values of this quantity in natural water. (10[1])In the case of infinite dilution, this quantity can (10[1])be predicted from the square root of ionic strength by the Debye-Huckel (-5[1])equation. This quantity equals 1 for mixtures that obey Raoult’s law. (10[1])This quantity corresponds to the fugacity coefficient in gases. For 10 points, name this quantity symbolized gamma that measures deviations of a mixture from ideality. ■END■