| 摘要 |
FIELD: thermodynamic analysis. ^ SUBSTANCE: invention relates to methods for determining thermodynamic, real, and conventional equilibrium constants of inorganic and organic substances employed in theoretical and applied chemistry fields. Method of determining conventional solubility products and ionic products comprises potentiometric titration wherein, in the course of individual potentiometric titration, limiting degree of proceeding of analytical reaction is achieved through synchronously decreasing concentrations of components to their limiting state and, when the titration potential jump disappears, one calculates molar concentration of component forming low-soluble compound in stoichiometry point and finds equilibrium concentration of the subject substance using following relationships: Msp = (100-Clim).Mdet.Vdet/(Vdet+Vtitr).100% and SMnAm = (100-Clim).Mdet.Mtitr/(n.Mdet + m.Mtitr).100%, where Clim denotes limiting degree of proceeding of an individual analytical reaction, mole/L; SMnAm solubility of low-soluble substance, mole/L; Mdet initial molar concentration of component to be determined, mole/L; Vtitr volume of titrant, ml; Mtitr molar concentration of titrant, mole/L; n and m are stoichiometric coefficients. From Msp and SMnAm, conventional solubility product and ionic product, respectively, are found taking into account m and n values for given salt. ^ EFFECT: simplified determination procedure and enabled estimation of determination error. ^ 5 tbl |
