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Jarl B Rosenholm - One of the best experts on this subject based on the ideXlab platform.

  • surface induced Electrolytic Dissociation of oxalic and phosphoric acid in mixed alcohol water solvents
    Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2011
    Co-Authors: Per Dahlsten, Marek Kosmulski, Jarl B Rosenholm
    Abstract:

    Abstract The electric conductance of solutions of oxalic, phosphoric and sulfuric acid (up to 0.025 M) in ethanol, methanol, and mixed alcohol–water solvents has been studied in the presence and absence of TiO2 (1–10% by mass). TiO2 enhanced the conductance of solutions of oxalic and phosphoric acid in anhydrous alcohol and in alcohol-rich mixed solvents. In water-rich mixed solvents “normal” behavior was observed, that is, TiO2 depressed the conductance of electrolyte solutions. The enhanced conductance is interpreted in terms of surface-induced Electrolytic Dissociation. In nonaqueous solvents, oxalic and phosphoric acid occur chiefly in molecular form, even in very dilute solutions. TiO2 binds the hydrogen oxalate or dihydrogen phosphate anions (which originate from neutral acid molecules) and the protons remain in solution in form of solvated cations. The lyonium cations have a substantially higher molar conductance than other ions due to the Grotthuss mechanism. This is why the enhancement of conductance is more substantial in solutions of weak acids than in solutions of other electrolytes.

  • Surface-induced Electrolytic Dissociation of oxalic and phosphoric acid in mixed alcohol–water solvents
    Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2011
    Co-Authors: Per Dahlsten, Marek Kosmulski, Jarl B Rosenholm
    Abstract:

    Abstract The electric conductance of solutions of oxalic, phosphoric and sulfuric acid (up to 0.025 M) in ethanol, methanol, and mixed alcohol–water solvents has been studied in the presence and absence of TiO2 (1–10% by mass). TiO2 enhanced the conductance of solutions of oxalic and phosphoric acid in anhydrous alcohol and in alcohol-rich mixed solvents. In water-rich mixed solvents “normal” behavior was observed, that is, TiO2 depressed the conductance of electrolyte solutions. The enhanced conductance is interpreted in terms of surface-induced Electrolytic Dissociation. In nonaqueous solvents, oxalic and phosphoric acid occur chiefly in molecular form, even in very dilute solutions. TiO2 binds the hydrogen oxalate or dihydrogen phosphate anions (which originate from neutral acid molecules) and the protons remain in solution in form of solvated cations. The lyonium cations have a substantially higher molar conductance than other ions due to the Grotthuss mechanism. This is why the enhancement of conductance is more substantial in solutions of weak acids than in solutions of other electrolytes.

  • surface induced Electrolytic Dissociation of weak acids in ethanol
    Journal of Physical Chemistry C, 2010
    Co-Authors: Marek Kosmulski, Piotr Prochniak, Edward Maczka, Jarl B Rosenholm
    Abstract:

    Positively charged particles of metal oxides (alumina, hematite, and titania) enhance the Electrolytic Dissociation of phosphoric, oxalic, citric, and succinic acids in 94% ethanol (by mass). This results in enhanced electric conductance of dispersions of these oxides, which is higher than the conductance of dispersion containing only solvent and metal oxide and of an alcoholic solution of a weak acid. This phenomenon is accompanied by a shift of the ζ potential of the oxide particles to more negative values. The changes in the ζ potential indicate strong positive adsorption of anions from solution.

  • surface induced Electrolytic Dissociation of oxalic acid in polar organic solvents
    Langmuir, 2010
    Co-Authors: Marek Kosmulski, Piotr Prochniak, Jarl B Rosenholm
    Abstract:

    The presence of titania powder (chiefly anatase) enhanced Electrolytic Dissociation of oxalic acid in lower aliphatic alcohols (but not in water). The surface-induced Dissociation was manifested in enhanced electric conductance of a dispersion containing solvent, oxalic acid, and titania, which was substantially higher than the conductance of dispersion containing only solvent and titania and of solution of oxalic acid in that solvent. This phenomenon can be applied to control the electrokinetic potential of particles in polar organic solvents.

Marek Kosmulski - One of the best experts on this subject based on the ideXlab platform.

  • surface induced Electrolytic Dissociation of oxalic and phosphoric acid in mixed alcohol water solvents
    Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2011
    Co-Authors: Per Dahlsten, Marek Kosmulski, Jarl B Rosenholm
    Abstract:

    Abstract The electric conductance of solutions of oxalic, phosphoric and sulfuric acid (up to 0.025 M) in ethanol, methanol, and mixed alcohol–water solvents has been studied in the presence and absence of TiO2 (1–10% by mass). TiO2 enhanced the conductance of solutions of oxalic and phosphoric acid in anhydrous alcohol and in alcohol-rich mixed solvents. In water-rich mixed solvents “normal” behavior was observed, that is, TiO2 depressed the conductance of electrolyte solutions. The enhanced conductance is interpreted in terms of surface-induced Electrolytic Dissociation. In nonaqueous solvents, oxalic and phosphoric acid occur chiefly in molecular form, even in very dilute solutions. TiO2 binds the hydrogen oxalate or dihydrogen phosphate anions (which originate from neutral acid molecules) and the protons remain in solution in form of solvated cations. The lyonium cations have a substantially higher molar conductance than other ions due to the Grotthuss mechanism. This is why the enhancement of conductance is more substantial in solutions of weak acids than in solutions of other electrolytes.

  • Surface-induced Electrolytic Dissociation of oxalic and phosphoric acid in mixed alcohol–water solvents
    Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2011
    Co-Authors: Per Dahlsten, Marek Kosmulski, Jarl B Rosenholm
    Abstract:

    Abstract The electric conductance of solutions of oxalic, phosphoric and sulfuric acid (up to 0.025 M) in ethanol, methanol, and mixed alcohol–water solvents has been studied in the presence and absence of TiO2 (1–10% by mass). TiO2 enhanced the conductance of solutions of oxalic and phosphoric acid in anhydrous alcohol and in alcohol-rich mixed solvents. In water-rich mixed solvents “normal” behavior was observed, that is, TiO2 depressed the conductance of electrolyte solutions. The enhanced conductance is interpreted in terms of surface-induced Electrolytic Dissociation. In nonaqueous solvents, oxalic and phosphoric acid occur chiefly in molecular form, even in very dilute solutions. TiO2 binds the hydrogen oxalate or dihydrogen phosphate anions (which originate from neutral acid molecules) and the protons remain in solution in form of solvated cations. The lyonium cations have a substantially higher molar conductance than other ions due to the Grotthuss mechanism. This is why the enhancement of conductance is more substantial in solutions of weak acids than in solutions of other electrolytes.

  • surface induced Electrolytic Dissociation of weak acids in ethanol
    Journal of Physical Chemistry C, 2010
    Co-Authors: Marek Kosmulski, Piotr Prochniak, Edward Maczka, Jarl B Rosenholm
    Abstract:

    Positively charged particles of metal oxides (alumina, hematite, and titania) enhance the Electrolytic Dissociation of phosphoric, oxalic, citric, and succinic acids in 94% ethanol (by mass). This results in enhanced electric conductance of dispersions of these oxides, which is higher than the conductance of dispersion containing only solvent and metal oxide and of an alcoholic solution of a weak acid. This phenomenon is accompanied by a shift of the ζ potential of the oxide particles to more negative values. The changes in the ζ potential indicate strong positive adsorption of anions from solution.

  • simple model of surface induced Electrolytic Dissociation of weak acids in organic solvents
    Adsorption-journal of The International Adsorption Society, 2010
    Co-Authors: Marek Kosmulski
    Abstract:

    The electric conductivity of solutions of oxalic and phosphoric acid (up to 0.025 M) in ethanol and methanol has been studied in the presence of TiO2 (1–10% by mass). TiO2 enhanced the conductivity of solutions of oxalic and phosphoric acid in the both alcohols. The experimentally observed behavior was successfully modeled using a model with two types of surface sites. Sites of the first type bind the acids in molecular form. Sites of the second type bind the acids in form of hydrogen oxalate and dihydrogen phosphate anions, respectively, and protons are released to the solution, and contribute to enhanced conductivity. The adsorption model properly reflects the electrokinetic potential of titania particles in alcoholic solutions of oxalic and phosphoric acid.

  • surface induced Electrolytic Dissociation of oxalic acid in polar organic solvents
    Langmuir, 2010
    Co-Authors: Marek Kosmulski, Piotr Prochniak, Jarl B Rosenholm
    Abstract:

    The presence of titania powder (chiefly anatase) enhanced Electrolytic Dissociation of oxalic acid in lower aliphatic alcohols (but not in water). The surface-induced Dissociation was manifested in enhanced electric conductance of a dispersion containing solvent, oxalic acid, and titania, which was substantially higher than the conductance of dispersion containing only solvent and titania and of solution of oxalic acid in that solvent. This phenomenon can be applied to control the electrokinetic potential of particles in polar organic solvents.

Rusudan Kurtanidze - One of the best experts on this subject based on the ideXlab platform.

  • the Electrolytic Dissociation of aryl derivatives of succinic acid
    Journal of Biomedical Science and Engineering, 2017
    Co-Authors: Elene Kvaratskhelia, Rusudan Kurtanidze
    Abstract:

    In this work, an analysis of the regularities of the Electrolytic Dissociation of aryl derivatives of the succinic acid (phenylsuccinic, benzylsuccinic, dibenzylsuccinic and phenyl-2-benzylsuccinic acids) in their dilute (0.0001 - 0.01 mol.dm-3) solutions was carried out with the aid of a new method of determination of the Dissociation parameters of weak multibasic organic acids with the “overlapping equilibria” effect previously described by authors. Values of the usual and “partial” degrees of Dissociation, the concentrations of all anions, hydrogen ions and undissociated acid molecules, the activity coefficients of all charged Dissociation products were calculated. Together with the accurate equations, the simple empirical equations for fast approximate determination of the various Dissociation parameters were also suggested.

  • the overlapping equilibria effect in the processes of the Electrolytic Dissociation of weak multibasic organic acids
    Journal of Biomedical Science and Engineering, 2014
    Co-Authors: Elene Kvaratskhelia, Ramaz Kvaratskhelia, Rusudan Kurtanidze
    Abstract:

    The “overlapping equilibria” effect observed in the processes of Electrolytic Dissociation of many weak multibasic organic acids determines the character of these processes. In this communication, the degree of “overlapping equilibria” in case of weak dibasic organic acids is quantitatively characterized by the values of “partial” degree of Dissociation for second step and ratio of the concentrations of dianion and monoanion. It has been shown that these Dissociation parameters are directly connected with the values of the second Dissociation constant. It has been also shown that the contribution of third Dissociation step in the “overlapping equilibria” effect is especially appreciable in case of penta and hexabasic weak organic acids causing the double “overlapping” phenomenon.

  • the regularities of Electrolytic Dissociation of weak dibasic and tribasic organic wine acids
    Journal of Applied Solution Chemistry and Modeling, 2013
    Co-Authors: Elene Kvaratskhelia, Ramaz Kvaratskhelia, Rusudan Kurtanidze
    Abstract:

    The weak dibasic and tribasic organic acids in wine: tartaric, malic, citric and succinic acids are the important components having direct influence on various properties of wine. The regularities of Electrolytic Dissociation of these acids determine all their useful properties. With the aid of suggested by authors original method for analysis the complex equilibria of the processes of Dissociation of weak multibasic organic acids the main Dissociation parameters of tartaric, malic, citric and succinic acids in their dilute solutions: the values of usual and “partial” degrees of Dissociation of all steps, the concentrations of all anions, hydrogen ions and undissociated acid molecules are determined. The concentration intervals of predominance of various charged and uncharged substances in dilute solutions of all above mentioned acids are also determined. The simple empirical equations for fast approximate calculation of the Dissociation degrees and pH values are also suggested.

  • the Electrolytic Dissociation of 1 2 cyclopentanedicarboxylic acids
    2014 ECS and SMEQ Joint International Meeting (October 5-9 2014), 2013
    Co-Authors: Elene Kvaratskhelia, Ramaz Kvaratskhelia, Rusudan Kurtanidze
    Abstract:

    Cyclopentanedicarboxylic acids are widely used in industry as pharmaceutical intermediates. Their useful properties are closely connected with the peculiarities of their behaviour in solutions and, consequently, with the regularities of their Electrolytic Dissociation which determine the distribution of biopharmaceutically active and inactive forms in their solutions. In this communication the analysis of the complex equilibria in the processes of Electrolytic Dissociation of isomeric cis and trans-1,2-cyclopentanedicarboxylic acids is carried out with the aid of original method suggested by authors for case of weak multibasic organic acids. For weak dibasic organic acids the law of dilution for both Dissociation steps may be expressed as follows:

  • the regularities of Electrolytic Dissociation of camphoric acid
    2010
    Co-Authors: Elene Kvaratskhelia, Ramaz Kvaratskhelia, Rusudan Kurtanidze
    Abstract:

    The parameters of Dissociation of camphoric acid in its dilute (0.0001-0.01M) solutions were deter- mined with the aid of original exact and approximate equations. © 2010 Bull. Georg. Natl. Acad. Sci.

Elene Kvaratskhelia - One of the best experts on this subject based on the ideXlab platform.

  • the Electrolytic Dissociation of aryl derivatives of succinic acid
    Journal of Biomedical Science and Engineering, 2017
    Co-Authors: Elene Kvaratskhelia, Rusudan Kurtanidze
    Abstract:

    In this work, an analysis of the regularities of the Electrolytic Dissociation of aryl derivatives of the succinic acid (phenylsuccinic, benzylsuccinic, dibenzylsuccinic and phenyl-2-benzylsuccinic acids) in their dilute (0.0001 - 0.01 mol.dm-3) solutions was carried out with the aid of a new method of determination of the Dissociation parameters of weak multibasic organic acids with the “overlapping equilibria” effect previously described by authors. Values of the usual and “partial” degrees of Dissociation, the concentrations of all anions, hydrogen ions and undissociated acid molecules, the activity coefficients of all charged Dissociation products were calculated. Together with the accurate equations, the simple empirical equations for fast approximate determination of the various Dissociation parameters were also suggested.

  • the overlapping equilibria effect in the processes of the Electrolytic Dissociation of weak multibasic organic acids
    Journal of Biomedical Science and Engineering, 2014
    Co-Authors: Elene Kvaratskhelia, Ramaz Kvaratskhelia, Rusudan Kurtanidze
    Abstract:

    The “overlapping equilibria” effect observed in the processes of Electrolytic Dissociation of many weak multibasic organic acids determines the character of these processes. In this communication, the degree of “overlapping equilibria” in case of weak dibasic organic acids is quantitatively characterized by the values of “partial” degree of Dissociation for second step and ratio of the concentrations of dianion and monoanion. It has been shown that these Dissociation parameters are directly connected with the values of the second Dissociation constant. It has been also shown that the contribution of third Dissociation step in the “overlapping equilibria” effect is especially appreciable in case of penta and hexabasic weak organic acids causing the double “overlapping” phenomenon.

  • the regularities of Electrolytic Dissociation of weak dibasic and tribasic organic wine acids
    Journal of Applied Solution Chemistry and Modeling, 2013
    Co-Authors: Elene Kvaratskhelia, Ramaz Kvaratskhelia, Rusudan Kurtanidze
    Abstract:

    The weak dibasic and tribasic organic acids in wine: tartaric, malic, citric and succinic acids are the important components having direct influence on various properties of wine. The regularities of Electrolytic Dissociation of these acids determine all their useful properties. With the aid of suggested by authors original method for analysis the complex equilibria of the processes of Dissociation of weak multibasic organic acids the main Dissociation parameters of tartaric, malic, citric and succinic acids in their dilute solutions: the values of usual and “partial” degrees of Dissociation of all steps, the concentrations of all anions, hydrogen ions and undissociated acid molecules are determined. The concentration intervals of predominance of various charged and uncharged substances in dilute solutions of all above mentioned acids are also determined. The simple empirical equations for fast approximate calculation of the Dissociation degrees and pH values are also suggested.

  • the Electrolytic Dissociation of 1 2 cyclopentanedicarboxylic acids
    2014 ECS and SMEQ Joint International Meeting (October 5-9 2014), 2013
    Co-Authors: Elene Kvaratskhelia, Ramaz Kvaratskhelia, Rusudan Kurtanidze
    Abstract:

    Cyclopentanedicarboxylic acids are widely used in industry as pharmaceutical intermediates. Their useful properties are closely connected with the peculiarities of their behaviour in solutions and, consequently, with the regularities of their Electrolytic Dissociation which determine the distribution of biopharmaceutically active and inactive forms in their solutions. In this communication the analysis of the complex equilibria in the processes of Electrolytic Dissociation of isomeric cis and trans-1,2-cyclopentanedicarboxylic acids is carried out with the aid of original method suggested by authors for case of weak multibasic organic acids. For weak dibasic organic acids the law of dilution for both Dissociation steps may be expressed as follows:

  • the regularities of Electrolytic Dissociation of camphoric acid
    2010
    Co-Authors: Elene Kvaratskhelia, Ramaz Kvaratskhelia, Rusudan Kurtanidze
    Abstract:

    The parameters of Dissociation of camphoric acid in its dilute (0.0001-0.01M) solutions were deter- mined with the aid of original exact and approximate equations. © 2010 Bull. Georg. Natl. Acad. Sci.

Kevin C. De Berg - One of the best experts on this subject based on the ideXlab platform.

  • The Development of the Theory of Electrolytic Dissociation
    Science & Education, 2003
    Co-Authors: Kevin C. De Berg
    Abstract:

    The theory of Electrolytic Dissociation proved to be one of the most controversial in the history of chemistry. This paper examines the evidence proffered by Arrhenius, van't Hoff, and Ostwald in favour of the theory and outlines the objections raised by Armstrong, Fitzgerald, and Pickering. The controversy revolved partly around the nature of the emerging new chemistry and has important implications for the study of the nature of science. Some important observations are made in relation to the teaching and learning of chemistry.