Objective, of forecasting

Closed type homogenous models determine equilibrium composition of only water and also the content and activity coefficients of its migration forms under the assigned thermodynamical conditions. Object of forecasting is usually any volume of well mixed water (for instance, individual sample or mix of different waters) of assigned analytical composition. The behaviour of nonpolar components, beside O, CO and H S, in these model as a rule is not considered. The content of such models depends on the set of basis components, selected calculation methods of activity coefficients and equations system (2.76)-(2.79) or (2.80)-(2.83). For reactions of complex-formation it is necessary to have constants equilibrium value base. Ozyabkin (1995) treats them as lower level models. Kraynov et al. (2004) call them thermodynamical. 

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