Aneta Spórna-Kucab

By Anna Maria Michałowska-Kaczmarczyk, Aneta Spórna-Kucab and Tadeusz Michałowski

The chapter refers to a general concept of solubility product Ksp of sparingly soluble hydroxides and different salts and calculation of solubility of some hydroxides, oxides, and different salts in aqueous media. A (criticized) conventional approach, based on stoichiometry of a reaction notation and the solubility product of a precipitate, is compared with the unconventional/correct approach based on charge and concentration balances and a detailed physicochemical knowledge on the system considered, and calculations realized according to generalized approach to electrolytic systems (GATES) principles. An indisputable advantage of the latter approach is proved in simulation of static or dynamic, two-phase nonredox or redox systems.

Part of the book: Descriptive Inorganic Chemistry Researches of Metal Compounds

By Anna Maria Michałowska‐Kaczmarczyk, Aneta Spórna‐Kucab and Tadeusz Michałowski

The generalized equivalent mass (GEM) concept, based on firm algebraic foundations of the generalized approach to electrolytic systems (GATES) is considered, and put against the equivalent “weight” concept, based on a “fragile” stoichiometric reaction notation, still advocated by IUPAC. The GEM is formulated a priori, with no relevance to a stoichiometry. GEM is formulated in unified manner, and referred to systems of any degree of complexity, with special emphasis put on redox systems, where generalized electron balance (GEB) is involved. GEM is formulated on the basis of all attainable (and preselected) physicochemical knowledge on the system in question, and resolved with use of iterative computer programs. It is possible to calculate coordinates of the end points, taken from the vicinity of equivalence point. This way, one can choose (among others) a proper indicator and the most appropriate (from analytical viewpoint) color change of the indicator. Some interpolative and extrapolative methods of equivalence volume Veq determination are recalled and discussed. The GATES realized for GEM purposes provides the basis for optimization of analytical procedures a priori. The GATES procedure realized for GEM purposes enables to foresee and optimize new analytical methods, or modify, improve, and optimize old analytical methods.

Part of the book: Advances in Titration Techniques

By Anna Maria Michałowska-Kaczmarczyk, Aneta Spórna-Kucab and Tadeusz Michałowski

This chapter refers to fundamental/general/obligatory regularities of electrolytic systems. The linear combination 2·f(O) − f(H) of elemental balances, f(H) for H and f(O) for O, provides a rigorous criterion distinguishing between redox and non-redox systems is presented as the general relation distinguishing between electrolytic redox and non-redox systems in aqueous media. As the linearly independent equation for a redox system, 2·f(O) − f(H) is considered as the primary form of the generalized electron balance (GEB), perceived as a law of nature, as the hidden connection of physicochemical laws and the breakthrough in thermodynamic theory of electrolytic redox systems. GEB completes the set of 2+K equations necessary for thermodynamic resolution of redox systems according to generalized approach to electrolytic systems (GATES) applying all relevant, physicochemical knowledge available. GATES/GEB, perceived as an example of excellent paradigm, provides the best thermodynamic approach to electrolytic redox systems of any degree of complexity, in aqueous, non-aqueous, and mixed-solvent media. The formulation of GEB does not need prior knowledge of oxidation numbers for all elements in components forming any electrolytic system, within GATES/GEB, the stoichiometry, oxidation number, oxidant, reductant and equivalent mass are as derivative concepts.

Part of the book: Redox