A new sensitive method of dissociation constants determination based on the isohydric solutions principle

Dynamic Buffer Capacities in Redox Systems

“…Buffered solutions are commonly applied in different procedures involved with classical (titrimetric, gravimetric) and instrumental analyses [30][31][32][33]. There are in close relevance to isohydric solutions [24][25][26] and pH-static titration [4,34], and titration in binary-solvent systems [12,35]. Buffering property is usually referred to an action of an external agent (mainly: strong acid, HB, or strong base, MOH) inducing pH change, ∆pH, of the solution.…”

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

“…pH interval Gran type functions Simple acid-acid systems are involved in isohydricity concept, formulated by Michalowski [31,32,79]. For the simplest case of acid-acid titration HB (C,V) !…”

“…On this basis, a very sensitive method of pK 1 determination was suggested [31,32]. The isohydricity conditions were also formulated for more complex acid-acid, base-base systems, etc.…”

“…The detailed considerations in this chapter are based on principles of the generalized approach to electrolytic systems (GATES), formulated by Michałowski [9] and presented recently in a series of papers, related to redox [7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26] and nonredox systems [27][28][29][30][31][32] in aqueous and in mixed-solvent media [33][34][35][36][37]. The closed system separated from its environment by diathermal walls secure a heat exchange between the system and its environment, and realize dynamic processes in a quasistatic manner under isothermal conditions.…”

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

“…However, the special, isohydricity property is attributed here to solutions of two different acids, A 1 and A 2 , or two different bases, B 1 and B 2 , having equal pH values, i.e., the term "isohydric" refers to solutions of the same hydrogen-ion concentration, [H +1 ]. After Arrhenius, such a pair of solutions is termed as isohydric solutions [3,4].However, the Arrhenius' statement [5], expressed in more contemporary terms, as "if two solutions of the same pH are mixed, pH of the mixture is unchanged, regardless the composition of the solutions" [6], is not true, when referred to any pair of electrolytic systems.As an example [7], let us take the pair of solutions: C 1 = 10 -2.5 ≈ 0.003 mol/L HCN and C 2 = 1 mol/L AgNO 3 .From the approximate formulae: [H +1 ] = (C 1 ⋅ K 1 ) 1/2 for HCN (C 1 ) and [H +1 ] = (C 1 ⋅ K 1 oH ⋅KW) 1/2 for AgNO 3 (C 2 ) we get pH=5.85, for both solutions; [AgOH] = K 1 OH [Ag +1 ][OH -1 ]), logK 1 OH = 2.3; [H +1 ][CN -1 ] = K 1 [HCN], pK 1 = 9.2; K W =[H +1 ][OH -1 ], pK W = 14. However, as were stated in [8], Ag +1 ions when added into HCN solution act as a strong acid generating protons, mainly in the complexation reaction Ag +1 + 2HCN = Ag(CN) 2 -1 + 2H +1 , and pH of the mixture drops abruptly.…”