scholarly journals The application of logarithmic charts when evaluating the equilibrium concentrations of all particles in acid-base systems

2021 ◽  
Vol 11 (1) ◽  
pp. 26-33
Author(s):  
B. B. Tanganov
Keyword(s):  
Ionic Strength ◽  
Material Balance ◽  
Mass Action ◽  
Temperature Structure ◽  
Hydrogen Ions ◽  
Acid Base ◽  
Electrical Neutrality ◽  
Aqueous Solvent ◽  
Acid Base Equilibrium ◽  
Equilibrium Concentrations

Until recently, due to the absence of other suitable approaches, equilibrium concentrations in acid-base systems have been studied exclusively by measuring the pH of a solution. However, this method can not be used for organic (non-aqueous) solvent solutions. It is known that the ionic strength of a solution, which is a fundamental component in assessing the activity coefficient and the thermodynamic dissociation constant of an electrolyte, is influenced by the ions present in the system. The concentration of these ions is variable during interactions in aqueous and more complex non-aqueous solutions, which differ significantly in their physicochemical properties (boiling temperature, structure, permittivity, autoprotolysis constant, solvating ability, dipole moment, viscosity, etc.). Meanwhile, in order to obtain more objective and valid estimates of acid-base interactions, in addition to the activity of hydrogen ions, appropriate account should be taken of the equilibrium concentrations of all particles in the solution, which affect its ionic strength. In this article, on the basis of the law of mass action and equations describing equilibrium processes, the ionic product of a solvent, electrical neutrality and material balance in a solution, the corresponding equations were derived and a method was proposed for considering the effect of the concentrations of all particles in the system (not only hydrogen ions – pH), significantly affecting the properties of acid-base equilibrium systems. The proposed method can also be used to obtain the dependence of the equilibrium concentrations of all process substances on the state of the medium (test solution), determined by various chemical and instrumental methods in logarithmic coordinates, which makes it pos-sible to directly assess the equilibrium concentra- tions of all particles present in the system.

scholarly journals Applied aspects of acid-base interactions and modelling equilibrium concentrations in two-component acid mixtures

2020 ◽  
Vol 10 (3) ◽  
pp. 393-400
Author(s):  
B. B. Tanganov
Keyword(s):  
Ionic Strength ◽  
Aqueous Solutions ◽  
Charged Particles ◽  
Material Balance ◽  
Mass Action ◽  
Develop Model ◽  
Acid Base ◽  
Ionic Product ◽  
Weak Electrolytes ◽  
Equilibrium Concentrations

Fundamental and applied research into aqueous and non-aqueous solutions of strong and weak electrolytes remains to be highly relevant, which fact is confirmed by a large number of Russian and foreign publications. In almost all such publications, acid-base interactions are considered exclusively with regard to changes in hydrogen ion concentrations. However, the ionic strength of solutions is determined by all ions present in the system, the concentration of which varies during interactions. This is particularly true for potentiometric titration of strong and weak electrolytes not only in aqueous, but also in more complex non-aqueous solutions, which differ significantly in their basic properties (dielectric constant, ionic product, dipole moment, viscosity, etc.). In the study of equilibria, it is more feasible to develop model representations that would greatly simplify and facilitate the computation and evaluation of certain properties of the system under consideration. In this work, acid-base interactions are presented in the form of equations based on mass action laws and those describing equilibrium processes, solvent ionic product, electroneutrality and material balance in electrolyte systems. The proposed equations consider the effect of the concentrations of all charged particles in the system (not only of hydrogen ions – pH) on the ionic strength of the solution, activity coefficients and, as a consequence, the thermodynamic dissociation constant. In addition, these equations allow the dependence between the equilibrium concentrations of all charged particles and the solution acidity determined by the potentiometric method to be expressed in convenient and objective logarithmic coordinates, thus facilitating estimation of the concentration of all particles at any moment of titration.

Acid−Base Equilibrium Constants for Glycine in NaClO4, KCl, and KBr at 298 K. Dependence on Ionic Strength

1998 ◽  
Vol 43 (5) ◽  
pp. 876-879 ◽  
Author(s):  
P. Alonso ◽  
J. L. Barriada ◽  
P. Rodríguez ◽  
I. Brandariz ◽  
M. E. Sastre de Vicente
Keyword(s):  
Ionic Strength ◽  
Equilibrium Constants ◽  
Acid Base ◽  
Base Equilibrium ◽  
Acid Base Equilibrium ◽  
Dependence On Ionic Strength

Synthesis, Acid-Base Properties, Kinetics and Mechanism of Cu2+ Incorporation into Water-Soluble Highly Substituted Porphyrins

2017 ◽  
Vol 21 (09) ◽  
pp. 611-621
Author(s):  
Hirofumi Konno ◽  
Jun Takeda
Keyword(s):  
Aqueous Solution ◽  
Ionic Strength ◽  
Kinetics And Mechanism ◽  
Water Soluble ◽  
Acid Base ◽  
Base Equilibrium ◽  
Absorbance Change ◽  
Acid Base Equilibrium ◽  
Kinetics Of ◽  
Base Properties

The synthesis, acid-base properties, and kinetics of Cu[Formula: see text] incorporation into water-soluble highly substituted porphyrins were studied. The basicity increased and the stepwise acid-base equilibrium was clarified by increasing the number of phenyl groups at the [Formula: see text] position, and the basicity of a dodeca-substituted porphyrin increased with the ionic strength. The metalation reaction of the dodeca-substituted porphyrin with Cu[Formula: see text] in aqueous solution revealed a biphasic absorbance change at 453 nm. Plots of [Formula: see text] or[Formula: see text] vs. the Cu[Formula: see text] concentration and of log ([Formula: see text] or[Formula: see text]/[Formula: see text] 0) vs. the ionic strength show that [Formula: see text] is dependent on the Cu[Formula: see text] concentration and ionic strength, while [Formula: see text] is independent of these parameters. These results confirm the stepwise metalation mechanism and the existence of an intermediate in aqueous solution, which is indicated by the biphasic absorbance change at 453 nm.

scholarly journals ADM1-based modeling of anaerobic codigestion of maize silage and cattle manure – a feedstock characterisation for model implementation (part I) / Modelowanie kofermentacji kiszonki kukurydzy i obornika bydlęcego za pomocą ADM1 – charakterystyka wsadu surowcowego (część I)

2015 ◽  
Vol 41 (3) ◽  
pp. 11-19 ◽  
Author(s):  
Ewa Klimiuk ◽  
Zygmunt Mariusz Gusiatin ◽  
Tomasz Pokój ◽  
Sabina Rynkowska ◽  
Keyword(s):  
Organic Matter ◽  
Nitrogen Concentration ◽  
Material Balance ◽  
Cattle Manure ◽  
Soluble Organic Matter ◽  
Maize Silage ◽  
Acid Base ◽  
Volatile Solids ◽  
Acid Base Equilibrium ◽  
Anaerobic Codigestion

Abstract This paper presents the results of fractionation of particulate and soluble organic matter in a mixture of maize silage and cattle manure (49:51% volatile solids) that was used as a feedstock for anaerobic digestion. The extended Weender’s analysis was adapted to measure raw protein, raw lipids, fraction of carbohydrates (including starch, cellulose, hemicelluloses) and lignin. The content of individual fractions in composite, Xc (as kg COD kg-1 COD) was: 0.111 proteins, 0.048 lipids, 0.500 carbohydrates and 0.341 inerts. The biodegradability of Xc was 68%. Based on material balance, the carbon concentration in Xc was 0.0326 kmol C kg-1 COD, whereas nitrogen concentration 0.0018 kmol N kg-1 COD. The estimated pH of the feedstock based on acid-base equilibrium corresponded to the actual value (pH 7.14).

scholarly journals A MECHANISM OF ADSORPTION OF HYDROGEN IONS ON SILK STUDIED BY ACID-BASE EQUILIBRIUM OF AN OPTICAL PROBE CONJUGATE

1981 ◽  
Vol 37 (3) ◽  
pp. T112-T118
Author(s):  
Nobuo Ikuta ◽  
Eisaku Nomura ◽  
Joichi Koga ◽  
Nobuhiko Kuroki
Keyword(s):  
Optical Probe ◽  
Hydrogen Ions ◽  
Acid Base ◽  
Base Equilibrium ◽  
Acid Base Equilibrium ◽  
Adsorption Of Hydrogen

scholarly journals The Importance of the Ionic Product for Water to Understand the Physiology of the Acid-Base Balance in Humans

2014 ◽  
Vol 2014 ◽  
pp. 1-16 ◽  
Author(s):  
María M. Adeva-Andany ◽  
Natalia Carneiro-Freire ◽  
Cristóbal Donapetry-García ◽  
Eva Rañal-Muíño ◽  
Yosua López-Pereiro
Keyword(s):  
Plasma Concentration ◽  
Ionic Composition ◽  
Relative Proportion ◽  
Compensatory Mechanism ◽  
Hydrogen Ions ◽  
Acid Base Balance ◽  
Acid Base ◽  
Electrical Neutrality ◽  
Ionic Product ◽  
Base Balance

Human plasma is an aqueous solution that has to abide by chemical rules such as the principle of electrical neutrality and the constancy of the ionic product for water. These rules define the acid-base balance in the human body. According to the electroneutrality principle, plasma has to be electrically neutral and the sum of its cations equals the sum of its anions. In addition, the ionic product for water has to be constant. Therefore, the plasma concentration of hydrogen ions depends on the plasma ionic composition. Variations in the concentration of plasma ions that alter the relative proportion of anions and cations predictably lead to a change in the plasma concentration of hydrogen ions by driving adaptive adjustments in water ionization that allow plasma electroneutrality while maintaining constant the ionic product for water. The accumulation of plasma anions out of proportion of cations induces an electrical imbalance compensated by a fall of hydroxide ions that brings about a rise in hydrogen ions (acidosis). By contrast, the deficiency of chloride relative to sodium generates plasma alkalosis by increasing hydroxide ions. The adjustment of plasma bicarbonate concentration to these changes is an important compensatory mechanism that protects plasma pH from severe deviations.

Spectrophotometric study of the interaction of Chromazurol S and Eriochromazurol B with surface active substances - tensides

1981 ◽  
Vol 46 (5) ◽  
pp. 1090-1106 ◽  
Author(s):  
Irena Burešová ◽  
Vlastimil Kubáň ◽  
Lumír Sommer
Keyword(s):  
Critical Micellar Concentration ◽  
Spectrophotometric Study ◽  
Conditional Stability ◽  
Acid Base ◽  
Binary Complexes ◽  
Chromazurol S ◽  
Acid Base Equilibrium ◽  
Poorly Soluble ◽  
Conditional Stability Constants ◽  
Triton X

The acid-base and optical properties of Chromazurol S and Eriochromazurol B in the presence of 1 . 10-6 - 2 . 10-2M solutions of cetylpyridinium bromide, cetyltrimethylammonium bromide and 1-ethoxycarbonylpentadecyltrimethylammonium bromide (Septonex) and 0.001-1.0% w/v solutions of octylphenolpolyethylene glycol ether (Triton X-100), polyoxyethylenemonolauryl ether (Brij 35) and lauryl sulphate sodium salt were determined by graphical and numerical interpretation of absorbance curves. The poorly soluble ion associates, which can be extracted into chloroform and which have the defined composition [LH4-nn-.n T+] or [LH3-nn-.n T+] are formed at submicellar concentration of the tenside. In regions close to the critical micellar concentration of the tenside, soluble binary complexes of the acid-base forms of the reagent are formed with tenside micelles. The conditional stability constants of the reagent acid-base equilibrium depend on the type and concentration of the tenside, on the reagent concentration, on the concentration and type of inorganic acid anions and on the ionic strength of the solution. The mechanism of interaction of the reagent with the tenside and the probable structure of the binary species are discussed.

Donnan Equilibria in Polymeric Micellar Systems with Weak Polyelectrolyte Shells: The Lowering of the pH Value

1997 ◽  
Vol 62 (11) ◽  
pp. 1730-1736 ◽  
Author(s):  
Petr Munk ◽  
Zdeněk Tuzar ◽  
Karel Procházka
Keyword(s):  
Ionic Strength ◽  
Block Copolymer ◽  
Ph Value ◽  
Electrolyte Solutions ◽  
Hydrogen Ions ◽  
Micellar Systems ◽  
Weak Electrolytes ◽  
Block Copolymer Micelles ◽  
Copolymer Micelles ◽  
Polyelectrolyte Solutions

When two electrolyte solutions are separated and only some of the ions can cross the boundary, the concentrations of these ions are different on both sides of the boundary. This is the well-known Donnan effect. When weak electrolytes are involved, the imbalance includes also hydrogen ions: there is a difference of pH across the boundary and the dissociation of nondiffusible weak electrolytes is suppressed. The effect is very pronounced when the concentration of the weak electrolyte is high and ionic strength is low. The significance of this phenomenon is discussed for polyelectrolyte solutions, and particularly for block copolymer micelles with weak polyelectrolyte shells. The effect is quite dramatic in the latter case.

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