Principles of Titrimetric Analyses According to Generalized Approach to Electrolytic Systems (GATES)

Abstract

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 a 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 V eq 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.

Stoichiometric approach to redox back titrations in ethanol analyses

“…Such a procedure is valid for the systems where the reaction leads to completion, as in the analysis speci ied in this paper. In general case, in particular when this requirement is not ful illed, a use of a more advantageous simulating approach, which involves all prior physicochemical knowledge about the system tested, is suggested; its use was illustrated in the authors' papers cited in [13][14][15][16].…”

“…Titrimetry is one of the oldest analytical methods, frequently applied in analytical practice [13][14][15][16]. However, when the rate of reaction between analyte and reagent is slow, or when the standard solution lacks stability, or when the end point cannot be detected in a simple way -direct titration is not possible and resort is made to backtitration.…”

Solubility Products and Solubility Concepts

“…Both approaches (I and II) to GEB were widely discussed in the literature [7-12, 14, 15, 17, 18, 34, 52-74], and in three other chapters in textbooks [75][76][77][78][79] issued in 2017 within InTech. The GEB is perceived as a law of nature [9,10,17,67,71,73,74], as the hidden connection of physicochemical laws, as a breakthrough in the theory of electrolytic redox systems.…”

Formulation of Isohydricity Conditions in Acid-Base systems - A Review

“…Correct equations, expressing the isohydricity property, were formulated by Michałowski and presented, for different systems, in a series of papers [3,4,7,17]. This was the basis of precise determination of dissociation constant values in pH-metric titrations, made both in aqueous [3] and binary-solvent [4,18] media.…”

“…The preliminary assumptions in isohydrocity formulation made by Carpéni [14] and then modified by McBryde [15] are unacceptable. In turn, de Levie introduced for this purpose the so-named proton condition, but the results of his clumsy trials, presented in [16], can be passed over in silence.Correct equations, expressing the isohydricity property, were formulated by Michałowski and presented, for different systems, in a series of papers [3,4,7,17]. This was the basis of precise determination of dissociation constant values in pH-metric titrations, made both in aqueous [3] and binary-solvent [4,18] media.…”