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Data on the phase concentration equilibrium are necessary to find out the direction of the process (drying or wetting of the material), calculate the kinetics of the drying process, and select storage conditions for the dried material. The paper presents the experimental isotherms of desorption of moisture from sunflower seeds of variety MAS 95.OL and from their components: kernels and shells—at temperatures of 24, 36, and 48°C. The studies were carried out by the static method using saturated salt solutions to create certain values of relative humidity in desiccators. It has been shown that seed shells have twice as much absorption capacity as kernels, due to differences in their morphological composition and structure. For the convenience of engineering calculations, the graphical equilibrium dependences were approximated by equations. By processing the obtained experimental data, a relationship is obtained between the equilibrium moisture contents of the nuclei and shells, which is linear in nature with a kink in the middle part of the equilibrium moisture contents. The boundary condition of mass transfer of the fourth kind (the condition of mass transfer conjugation) is given, which should be formulated when formulating the mathematical problem of drying a single seed that considers the seed as a two-layer body. [ABSTRACT FROM AUTHOR]

A comparative σρ analysis was made of the experimental characteristics of the gas-phase (ΔGgas)'liquid-phase (pKa), kinetic (logkD) acidity of normal CH acids of various structures (terminal acetylenes'substituted benzenes, and methane derivatives CH3X, CH2X2, and CH2XY, where substituents X and Y areelectron acceptors). The approach to interpretation of the correlation results took into account the concept of hard and soft acids and bases. The results of the σρ correlation analysis of ΔGgas, pKa, and logkD of terminal acetylenes, allowing a common description of the effect of structural factors on these quantities with induction σI constants, suggest uniformity of the electronic interactions. As a consequence, there are no thermodynamic deviations from the Brønsted relationship. The correlations of ΔGgas and pKa of substituted benzenes, and also of methane derivatives forming nonplanar carbanions, suggest the prevalence of the induction effect on these quantities; however, the resonance effect makes an increased contribution to logkD. This difference in the behavior of the characteristics of the CH acidity is consistent with the conclusion made in the previous paper that the interactions in these compound series are characterized by solvation nonuniformity. For methane derivatives forming planar carbanions, the main mechanism of stabilization of these species in the gas phase, DMSO solution, and transition state of the reaction is the resonance effect. The experimentally observed deviation from the linearity of the Brönsted relationship is in this case also attributable to the nonuniformity of the interactions. The solvation interaction responsible for variation of pKa in DMSO depends on the contributions of the electrostatic factor and H bonding, whereas the solvation interaction responsible for variation of logkD involves only a certain fraction of the covalent bonding with a hydroxyl-containing solvent in the transition state of the reaction. [ABSTRACT FROM AUTHOR]

The following characteristics of 2-ethylhexanoic acid N′,N′-dialkyl(C4–C8)hydrazides relevant to their potential application as Cu(II) extractants were studied: solubility, acid-base properties, resistance to hydrolysis, loss with the aqueous phase, and distribution ratio in relation to the composition of the medium and length of alkyl chains. [ABSTRACT FROM AUTHOR]

Processes of extraction of ions of the I-IV group metals from acidic water solutions with paraffin quasiliquid emulsions containing neutral phosphorylazapodand, bis(dioctylphosphorylmethyl)-1,8-diamino-3,6-dioxaoctane I, and acidic components, bispentadecylphosphoric II and hexadecylsulfonic acid III is studied. High effectiveness of extraction of metal ions with these extraction compositions is established. It significantly exceeds the effectiveness of liquid extraction in the same systems, especially of ions of the II group metals. The extraction of three-charged ions proceeds more effectively by the mixture of organophosphorus reagents I and II, than with the composition consisting of azapodand I and organosulfur acid III. [ABSTRACT FROM AUTHOR]

Solid complexes have been prepared and characterized by IR, UV-Vis, elemental analysis, and H NMR. Indomethacin forms complexes with Cd(II), Ce(III), and Th(IV) ions in molar ratios (ligand: metal) (2: 1), (3: 1), and (4: 1), respectively. The IR spectra of the complexes suggest that the Indomethacin behaves as a monobasic monodentate ligand coordinated to the metal ions via the deprotonated carboxylate group. Prepared complexes exhibit higher antimicrobial activity against several microorganisms, compared to free ligand. [ABSTRACT FROM AUTHOR]

We present the first study of Mn(II) cations interaction with ozone fed onto the air/aqueous manganese acetate solution boundary. In the reaction, the layer of HMnO· nHO of birnessite structure has been formed at the surface. Subsequent ∼1-3 μm thick layers drying at air has led to their rolling up to form microtubes with diameter of 20-50 μm and up to 10 mm long. [ABSTRACT FROM AUTHOR]

Acid-base properties of newly and previously synthesized phosphorylated azapodands and α,ω-diamines and their amine precursors were studied. We found that they differ in the same range as has been found previously for the other aminophosphoryl compounds. The investigation of the processes of passive membrane ion transport of a series of metals of I-III groups by these reactants showed with all diphosphoryl diamines higher values of the transfer flow of the ions Sc(III), Nd(III), and Sm(III), than the ions of alkali and alkaline earth metals. Under the conditions of active membrane transport the azapodand IV exhibits high efficiency in the ion transport of Sr(II) and Ba(II), while diphosphoryldiamine III exhibits effective transport of Nd(III) ions. The factors that determine the efficiency and selectivity of the membrane extraction of the I-III groups metal ions by these diphosphoryl diamines are discussed. [ABSTRACT FROM AUTHOR]

Thermochemistry of hydration of the aliphatic and aromatic amines was studied. Enthalpies of solution at infinite dilution of amines in water were measured using the method of solution calorimetry. A procedure of taking into account the ionization and non-specific hydration of amines in aqueous media was carried out. A method for estimating the enthalpy of hydrogen bonding of amines in aqueous solutions was suggested on the basis of a comparative analysis of the solvation enthalpies of the solutes in water and methanol. The efficiency of this method is confirmed by evaluating the hydrophobic effect enthalpy. [ABSTRACT FROM AUTHOR]

Published data are generalized on different research methods for structural characterization of the nearest surrounding of trivalent and tetravalent actinide ions in aqueous solutions of their salts under standard conditions. The structural parameters such as coordination numbers, interparticle distances, the parameters of the second coordination sphere, and the types of ionic association are discussed. The quantitative characteristics of hydrated complexes of poorly known trivalent actinide ions are determined on the basis of comparative analysis with lanthanide ions. [ABSTRACT FROM AUTHOR]

Using pycnometric method, we have measured density of the solutions of acrylic acid in acetonitrile, 1,2-dichloroethane, hexane, and benzene at 293 K and atmospheric pressure. The values of the excess molar volume for these systems and the values of the partial molar volumes of components were derived. In the whole concentration range the excess molar volume for binary mixtures of acrylic acid and either 1,2-dichloroethane, or benzene, or hexane has positive values, and in the system of acrylic acid-acetonitrile the value is negative. [ABSTRACT FROM AUTHOR]

The yield orotic aldehyde at the oxidation of 6-methyl-2,4-dihydroxypyrimidine was found to increase when selenious acid is used as an oxidizer. A comparative analysis of 6-methyl-2,4-dioxypyrimidine oxidation with selenium dioxide and selenious acid was performed using the ab initio quantum chemical method in the 6-31G** basis. [ABSTRACT FROM AUTHOR]

A convenient and effective one-pot three-component synthesis of the lead sulfide nanoparticles was developed on the basis of the exchange reaction between the lead acetate and sodium sulfide in water at the ambient conditions. A possibility was shown of the direct reaction between the lead Pb and sulfide S ions in an aqueous solution, resulting in a solid phase which contained PbS nanoparticles only, avoiding the hydrolysis stage. [ABSTRACT FROM AUTHOR]

The quantum-chemical DFT calculations of thermodynamic characteristics of the reactions of formation of binuclear dihydroxobridging [Fe(H2O)4(μ-OH)2Fe(H2O)4] n+ and oxobridging [Fe(H2O)5(μ-O)Fe·(H2O)5] n+ ( n = 2, 4) cations, the hydrolysis products of cations [Fe(H2O)6] m+ ( m = 2, 3). It is shown that effects of solvation lead to higher energetic stability of the dihydroxobridging binuclear compounds in aqueous solutions. [ABSTRACT FROM AUTHOR]

Results of photochemical precipitation of copper nanoparticles on the surface of polybutoxytitanium film applied to the surface of quartz sublayer and modified by the UV irradiation with the excitation wavelength 254 nm are presented. Photocatalytic activity of polybutoxytitanium film modified by the UV light was confirmed. It was established that photoprecipitated copper nanoparticles form a uniform stable coating consisting of tightly packed particles of 50 nm diameter and 8 nm height. [ABSTRACT FROM AUTHOR]

Synthesis and properties of a series of graft polyoxyalkylene-polyorganosiloxane block copolymers of various composition and structure were considered, and their surfactant properties were determined. The surface tension (σ) of the compounds obtained is shown to vary from 32.3 to 20.2 mN m−1. In aqueous solutions they behave as very effective surfactants. Thus, in several cases values of σ (19.7 mN m−1) observed were lower than those of organic surfactants (28.6–30.4 mN m−1). Their solutions in water or organic solvents show a significant decrease in wetting angle on glass. [ABSTRACT FROM AUTHOR]

The survey is dedicated to the critical analysis of different experimental methods of determining the dissociation constants (Ka) of organic acids in solutions. Advantages and disadvantages of the contemporary methods of rapid analysis used in biochemistry are considered. Special attention is paid to the problems of measurements in the nonaqueous media and to the reasons for possible incorrect results. The processes in solutions that should be taken into account for obtaining the correct values of dissociation constant are analyzed. On the basis of the consideration the recommendations directed toward an increase in the accuracy of measurements are given. [ABSTRACT FROM AUTHOR]

Results of investigations by the integral equation method in the XRISM approximation of features of structure formation in sub- and supercritical 0.5 M aqueous solution of RbBr. As the system passes from the sub- to supercritical state, the tetrahedral network of the solvent is destroyed, which is typical of water and aqueous solutions; thermal dehydration of the cation and anion are also observed. Dehydration is accompanied by contraction of the first hydration sphere of Rb+ and extension of the first hydration sphere of Br−. Both in sub- and supercritical solutions conditions a minor amount of contact ion pairs is present whose fraction is Higher by 15% compared to that in standard conditions. [ABSTRACT FROM AUTHOR]

Thermal decomposition of 3,3,6,6-tetramethyl-1,2,4,5-tetraoxane was examined in methanol solution (1.69×10−2 M) containing cuprous ions (5.05×10−7 M) in the temperature range from 130 to 166°C using UV spectroscopy as analytical method. The ion-catalyzed reaction follows first-order kinetics with respect to the peroxide and added cuprous ions. The temperature effect on the rate of thermal decomposition of the title compound was described by the corresponding Arrhenius equations, and its stability in solution was estimated on a quantitative level. The activation parameters of the initial step of decomposition of 3,3,6,6-tetramethyl-1,2,4,5-tetraoxane were determined (Δ H ≠ = 14.7±0.8 kcal mol−1; Δ S ≠ = −38.9±1.4 cal mol−1 K−1; Δ G ≠ = 31.0±0.8 kcal mol−1). Electron-transfer mechanism was proposed for the reaction under study. [ABSTRACT FROM AUTHOR]

Appearance of composite bands consisting of two individual bands with different half-widths in the course of resolution of absorption spectra was analyzed. [ABSTRACT FROM AUTHOR]

The contributions from interaction and reorganization to the enthaplies of solvation of polar and nonpolar nonelectrolytes in aqueous solutions of formamide, ethanediol, and 1,2-propanediol, forming 3D-associated structures in the entire composition range, were calculated. The enthalpy terms of the solvation of nonelectrolytes in aqueous solutions of methyl-and dimethylformamide were estimated. The data were compared considering the thermodynamic characteristics of these aqueous systems that we determined previously. It was found that the shape of the concentration dependences of the enthalpies of solvation of nonelectrolytes in all the examined solutions is determined by the reorganization term. The fact that the solvation of nonelectrolytes in water is the most exothermic compared to the aqueous-organic systems under consideration is due to the lowest value of the reorganization term in water, despite the fact that nonelectrolytes interact with water more weakly than with the nonaqueous components. [ABSTRACT FROM AUTHOR]

The kinetics of reduction of the azomethine bond in various Schiff bases and their transition metal complexes with sodium borohydride in dimethylformamide and ethanol solutions was studied. The reduction rate depends on both the structure of the starting Schiff bases and the nature of the metal ion. In transition metal N-phenylsalicylaldiminates, the rate of reduction of the azomethine group increases in the order Zn(II) < Ni(II) < Cu(II) < Co(II) < VO(II) < Mn(II). Similar trend is observed in other series of metal complexes with Schiff bases. The revealed trends are opposite to the Irving-Williams series of stability of complexes. This fact suggests that the major factor affecting the rate of reduction of the coordinated azomethine bond is the strength of its bonding with the metal ion. Depending on particular metal ion, the complexation can either decelerate or accelerate the reduction. [ABSTRACT FROM AUTHOR]

Solubility isotherms for the tetrabutylammonium chloride tetrabutylammonium hydroxide water system at 17 and 20°C were studied to reveal formation of two series of solid solutions on the basis of tetragonal (salt-water, 1 : 32) and cubic (1 : 28) clathrate hydrates. The nature of halide anions affects the formation of solid substitution solutions in the tetrabutylammonium hydroxide-tetrabutylammonium halide (F−, Cl−, Br−)-water system series. [ABSTRACT FROM AUTHOR]

Molar volumes in solutions at infinite dilution were determined for a series of intracomplex compounds of beryllium, zinc, cobalt, copper, and nickel, derived from salicyalalanilines, salicylalalkylimines, N-[(2-hydroxyphenyl)(methyl)methylene]anilines, N-[(2-hydroxyphenyl)(phenyl)methylene]aniline, as well as ethylene glycol and glycerol. An additivity scheme was constructed for calculation of the molar volumes of these compounds in solutions. Analysis of the experimental molar volumes of the systems studied showed that chelation via intramolecular complex formation almost always makes these values lower than those calculated by the additivity scheme, implying entropy stabilization of the chelates in solutions due to release of solvent molecules from the solvation shell of the molecules. It was shown that the dipole moments and Kerr constants of those compounds for which the additive scheme for calculation of molar volumes was constructed can be much easier estimated. [ABSTRACT FROM AUTHOR]

The molar volumes in solutions at infinite dilution were determined for a series of vinyl, glycol, isoprene, and cyclopentadiene polymers and oligomers with various degrees of polymerization. An additive analysis of the molar volumes showed that molecules of vinyl, ethylene glycol, and isoprene polymers exist in solutions in elongated helical conformations. In the majority of polymer molecules, except polystyrenes, polyisoprenes, and polycyclopentadienes, there are randomly disordered regions creating additional volumes inaccessible to solvation with solvent molecules. Cyclopentadiene oligomers formed by the Diels-Alder reaction have in solution the conformation of corrugated bands. The additive scheme for calculating the molar volumes considerably simplifies the determination of the dipole moments and Kerr constants of the compounds for which this scheme has been constructed. [ABSTRACT FROM AUTHOR]

The influence of physicochemical properties of solvents on the solubility of radon in them can be described by multiparameter linear equations taking into account various solvent characteristics; the decisive (and negative) effect on the radon solubility is exerted by the cohesion energy density and polarity of the solvent. This approach is efficient for summarizing data on the distribution ratios of radon between organic and aqueous phases. [ABSTRACT FROM AUTHOR]

The solubility of Kr in H2O-CD3OH-CO(NH2)2 and D2O-CH3OD-CO(ND2)2 mixtures in the entire range of compositions of the mixed aqueous-methanol solvent at a urea content of up to 1.5 solvomolality units (mole fraction 0.0263) was measured at 101 325 Pa and 278.15–318.15 K (at 10 K step). The standard Sechenov parameters K of the solubility of Kr and the thermodynamic parameters of krypton-urea pair interactions were determined. A differentiating effect of the H/D isotope substitution on K was revealed: Upon deuteration of groups participating in strong hydrogen bonding, the Sechenov solubility parameter increases, and upon replacement of CH3 by CD3, decreases in the absolute value. [ABSTRACT FROM AUTHOR]

2,3-Bis( p-methoxybenzoyl)cyclopentadiene was studied as iron(III)-chelating agent. Its p K a value was determined by spectrophotometry (p K a = 8.27 ± 0.02 at 25 ± 0.1°C; λ = 421 nm). 2,3-Bis( p-methoxybenzoyl)cyclopentadiene reacts with Fe3+ ions in aqueous ethanol (1:1, by volume) to give a 2:1 ligandmetal complex. The effects of different factors on the complex formation were studied. The reaction of 2,3-bis( p-methoxybenzoyl)cyclopentadiene with Fe3+ ions can be used as an alternative method for spectrophotometric determination of iron(III) in a range of concentrations from 0.1 to 1 μg cm−3, where the Beer law is fulfilled with a correlation coefficient of 0.9992. The results of spectrophotometric determination of iron(III) in geological materials (iron rock) showed very good agreement with those obtained by the atomic absorption measurements. [ABSTRACT FROM AUTHOR]

Solvation and complexation of Cu(II), Ni(II), and Co(II) with adipic acid dihydrazide (L) in aqueous and aqueous-ethanol solutions (ethanol mole fraction 0.07–0.68) were studied by spectrophotometry. The formation constants of the species M(LH)3+, ML2+, M2L4+ (μ = Cu2+, Ni2+, Co2+), and also M2L and ML (μ = Cu2+, Ni2+) were determined. With Cu(II), the complexes Cu(LH), CuL(LH)3+, and Cu2L(LH)5+ were also detected and characterized. Evidence is given for the hydrazide coordination mode: tridentate in ML2+, bidentate in M(LH)3+ and ML, and tetradentate in M2L4+ and M2L. The ligand exchange reactions involving CuL2+, Cu(LH)3+, Cu(LH), CuL(LH)3+, CuL, and Cu2L(LH)5+ in aqueous solutions of Cu(II) were revealed and kinetically characterized by nuclear magnetic relaxation. The heretofore unknown rate constants of formation of these complexes were calculated from the thermodynamic and kinetic parameters. Factors controlling the rate constants of the complex formation and chemical exchange are discussed. [ABSTRACT FROM AUTHOR]

The enthalpies of hydration and solution of organic substances in water at infinite dilution cannot be quantitatively characterized using any single correlation parameter. A correlation analysis using linear multiparameter equations shows that these quantities are governed by the combined effect of the nonspecific and specific solvation and the molar volume. [ABSTRACT FROM AUTHOR]

The interaction of ampicillin with the Mn2+, Co2+, and Ni2+ ions in aqueous solution at 20°C (supporting electrolyte 0.1 M KNO3) was studied pH-metrically and spectrophotometrically. In weakly acidic and neutral media, Ni2+ forms with the anionic ampicillin species 1: 1 and 1: 2 complexes, whereas Mn2+ and Co2+ form only 1: 1 complexes. The stability constants of the complexes were determined, and their possible structures were discussed. [ABSTRACT FROM AUTHOR]

In weakly acidic and neutral media, Zn2+ and Cd2+ ions form 1: 1 chelates with ampicillin in the anionic form; the ligand is coordinated through amino and anionic carboxylate groups. [ABSTRACT FROM AUTHOR]

The H/D isotope effects in the thermodynamic functions of solvation of N2 and O2 were calculated from the experimental data on the solubility of these nonpolar gases in H2O and D2O at ∼0.1 MPa and 278–318 K. The sharp increase in the solubility in going from N2 to O2 is caused both by a decrease in the contribution of the hydrophobic hydration and by the possibility of formation of H-type bonds by oxygen molecules with the aqueous environment. [ABSTRACT FROM AUTHOR]

The extraction of Au(III), Pt(IV), and Pd(II) ions from aqueous hydrochloric acid solutions with solutions of bis(2-ethylhexyl) N-butyl- N-octylaminomethylphosphonate in chloroform and xylene was studied. The recovery of the noble metal ions is the most efficient at low acidities of the aqueous solution, with a high selectivity of separation from the concomitant Fe(III), Cu(II), Ni(II), and Co(II) ions. [ABSTRACT FROM AUTHOR]

The interactions in the systems H2O-Am-SO2 (Am is formamide, dimethylformamide, acetamide, urea, tetramethylurea, tert-butylurea) at 278 and 293 K were studied pH-metrically. The results suggest formation of intermolecular and ion-molecule associates. The composition and stability of the compounds formed strongly depend on the structure and concentration of the solution components and on temperature. [ABSTRACT FROM AUTHOR]

The solubility of ammonium chloride in acetonitrile, dioxane, and 2-propanol in the range 298.15–338.15 K was determined using 36Cl tracer. The influence of properties of nonaqueous solvents on the solubility of ammonium, potassium, and sodium chlorides was subjected to thermodynamic and correlation analysis. The low solubility of ammonium chloride in dioxane and acetonitrile is due to the endothermic effect, and its high solubility in 2-propanol, to the exothermic effect of the salt solution. The entropy of solution affects the solubility of ammonium chloride in acetonitrile only slightly, in contrast to dioxane and 2-propanol in which the entropies of solution are significant and have opposite signs. The solubility of ammonium and potassium chlorides depends on the electron-acceptor power of the solvents and electrostatic interactions in solution, whereas the solubility of sodium chloride in organic solvents is determined by the combined influence of the donor-acceptor and dielectric properties of the solvents. [ABSTRACT FROM AUTHOR]

According to the results of quantum-chemical and correlation studies, ionized states of Alizarin and Alizarin Red are contributed mainly by tautomeric anthraquinoid structures. The probability of their formation increases due to solvation. The experimental electronic absorption spectra of the corresponding anions contain bands typical of the 2,9-, 1,10-, and 1,2-anthraquinoid tautomers. The 9,10-anthraquinoid structure of the anions is less probable. [ABSTRACT FROM AUTHOR]

The structural features of concentrated aqueous solutions of MeCl (Me = Li, Na, K, Rb; molar ratio [salt] : [water] = 1 : 15) at 293 K and 0.1 MPa were studied by the method of integral equations. The calculation results show that the disordering effect of the cation on the solvent structure grows in the order NaCl < KCl < RbCl (the number of free water molecules grows, and the content of tetrahedrally ordered molecules decreases). With LiCl, the changes in these parameters are maximal. In the systems containing Li+ and Na+ ions, the association parameter is lower than in pure water, whereas in the solutions with the K+ and Rb+ ions it is higher, in agreement with the concept of positive and negative hydration. It was suggested that, with increasing cationic radius, formation of hydrogen bonds between bulk water molecules becomes more preferential, and interactions between the anion and solvent molecules are weakened. On the contrary, the coordination number of the cation increases with its radius. In the examined series of solutions, the probability of formation of contact ion pairs grows considerably, and that of formation of hydration-separated ion pairs decreases. [ABSTRACT FROM AUTHOR]

Contact of thin layers of gelatin-immobilized copper(II) hexacyanoferrate(II) matrices with aqueous solutions of Co(II), Ni(II), Zn(II), and Cd(II) chlorides results in partial substitution of these ions for Cu(II) to give (dd)-heterobinuclear hexacyanoferrates(II) of copper(II) and the corresponding double-charged ion. [ABSTRACT FROM AUTHOR]

The results of a QSPR study of the toxicity of carboxylic acids in aqueous solution are reported. The molecular set comprises 35 carboxylic acids with the corresponding pKa values in water. The set of molecular and topological parameters includes electrotopological state of the carboxy and methyl groups, molar refractivity, refractive index, n-octanol-water partition coefficient logKo/w, surface tension, and polarizability. Quite reasonable estimates are obtained, which improve the results of previous theoretical calculations. [ABSTRACT FROM AUTHOR]

Ion exchange of silver(I) on thin polycrystalline PbS films in 10-5-10-2 M aqueous solutions of AgNO3 at 20-60°C was studied by X-ray fluorescence, atomic-absorption, and X-ray diffraction methods and by transmission electron microscopy. Since, under the given experimental conditions, diffusion of Ag(I) ions in a solid is the limiting stage of the process, the experimental kinetic dependences can be adequately described by the Fick equation for both “semi-infinite medium” and “restricted plane” at “steady source” of a diffusant on the surface. [ABSTRACT FROM AUTHOR]

The effect of dielectric and chemical (donor-acceptor interactions, cohesion energy density) properties of aqueous-organic solvents (water-methanol, water-2-propanol, water-acetonitrile, water-acetone, water-dioxane) on the thermodynamic functions of complexation of sodium and potassium cations with 18-crown-6 ether at 298 K was subjected to overall correlation analysis. [ABSTRACT FROM AUTHOR]

The solution enthalpies of ten polar nonelectrolytes in water preliminarily exposed to a weak magnetic field were measured and compared with thermodynamic data for water and heavy water. The observed regularities provide evidence showing that magnetization affects physicochemical properties of water. [ABSTRACT FROM AUTHOR]

Thermochemical characteristics of solution of copper(II) chloride were found from calorimetricdata, values describing solvation processes in a water-acetonitrile mixed solvent were calculated for theentire range of compositions. Enthalpy characteristics of solvation of individual Cu2+ ions in water-aceto-nitrile mixtures were found and analyzed. [ABSTRACT FROM AUTHOR]

Kinetics of heterolysis of 1-bromo-1-methylcyclopentane and -cyclohexane in protic and aprotic solvents were studied. Correlation analysis of the effect of solvent parameters on ΔG≠, ΔH≠, and ΔS≠ was performed. [ABSTRACT FROM AUTHOR]

The integral enthalpies of solution of Bu4NI in acetonitrile were determined experimentally in a wide range of concentrations and in the temperature range 233-323 K. The differential and standard enthalpies of solution of Bu4NI in acetonitrile were calculated. The changes in the enthalpies and heat capacities on solvation of a stoichiometric mixture of Bu4N+ and I- ions are primarily contributed by the long-range electrostatic ion-ion interaction. [ABSTRACT FROM AUTHOR]

The rate constants of the reaction of MeI with hydroxide ion at 298-323 K in aqueous isopropanol (isopropanol content 0-30 mol %) were measured. The effects of solvation of the reactants and activated complex were separated. The contributions of particular types of interactions to the solvation of the charged species were calculated. The results were compared with data for three other water-organic solvent systems. [ABSTRACT FROM AUTHOR]

Data on the solubility of 4,4′-isopropylidenediphenol in organic solvents can be quantitatively correlated with a linear three-parameter equation. The parameters exerting a decisive effect on the solubility are the polarity and basicity of solvents, favoring formation of intermolecular hydrogen bonds. At the same time, an increase in the cohesion energy of the medium decreases the solubility of the title compound. [ABSTRACT FROM AUTHOR]