Osmotic Coefficients Of Aqueous Solutions Research Articles

Aqueous solutions containing amino-acids and peptides. Part 3.—The osmotic coefficient at the freezing temperature of the solutions of aqueous systems containing glycine and some alkali metal chlorides and some tetra-alkylammonium bromides

The freezing temperature method has been used to determine the osmotic coefficients of aqueous solutions containing the single solutes tetramethylammonium, tetraethylammonium, tetra-n-propylammonium and tetra-n-butylammonium bromides. The results obtained are compared with those of other tetra-alkylammonium halides. The same experimental technique has been used to investigate binary solute aqueous systems containing glycine and LiCl, KCl, CsCl and the tetraalkylammonium bromides above. The results obtained are discussed from the viewpoints of the Kirkwood approach to systems containing ions and amino-acids and the McMillan—Mayer treatment of solutions.

Ion Association of Some 2 : 2 Electrolytes in Water at 25 °C. I. Studies of Magnesium, Calcium, Manganese, and Tris(1,10-phenanthroline)-ruthenium(II) Sulfate Solutions with a Vapor-Pressure Osmometer

Abstract The osmotic coefficients of aqueous solutions of magnesium, calcium, manganese, and tris(1,10-phenanthroline)ruthenium(II) sulfates were measured at 25 °C by means of a vapor-pressure osmometer. Then the ionassociation constants of these electrolytes were obtained as a function of the closest distance of approach of ions from the measured osmotic coefficients as well as from the available conductivity and cryoscopy data. The best values of the closest distance of approach and the ion-association constant (given in Table 6) were estimated with the help of theories of ion association. The formation of triple-ions and quadrupoles and the hydration of ions are also discussed in connection with the ion-association constant.

The osmotic coefficients of aqueous solutions of caesium chloride at the freezing temperatures of the solutions

The osmotic coefficients of aqueous solutions of caesium chloride at the freezing temperatures of the solutions

Osmotic coefficients and activity coefficients of lodic acid at high concentrations

Isopiestic vapor pressure measurements have been used to determine the osmotic coefficients of aqueous solutions of iodic acid at molalities from 0.1 to 17 mole-kg−1 at 25°C. The isopiestic standards were solutions of sodium chloride and solutions of sulfuric acid. Because of the corrosive nature of iodic acid, platinum cups were used. Stoichiometric activity cofficients of iodic acid were derived by a Gibbs-Duhem integration. The activity coefficients for solutions of molality greater than 0.5 mole-kg−1 cannot be accounted for in terms of the two equilibria, namely, the acidic dissociation of iodic acid and formation of the ion H(IO3)2−, shown by Pethybridge and Prue to explain adequately the behavior in dilute solutions. The activity coefficient is unexpectedly small in concentrated solutions, suggesting the formation of neutral aggregates of iodic acid. The presence of dimers and tetramers, or alternatively trimers and tetramers, can explain the observed results up to a molality of 7 mole-kg−1.

Osmotic coefficients of aqueous solutions of seven compounds at 0.deg.

Osmotic coefficients of aqueous solutions of seven compounds at 0.deg.

Osmotic coefficients of aqueous solutions of sodium bromide, sodium iodide, potassium fluoride, and calcium chloride between o.deg. and 90.deg.

Osmotic coefficients of aqueous solutions of sodium bromide, sodium iodide, potassium fluoride, and calcium chloride between o.deg. and 90.deg.

Excess Gibbs energy of mixing of the systems H2O-LiCl-Na2SO4 and H2O-CsCl-Na2SO4 at 25�C

The osmotic coefficients of aqueous solutions of lithium chloride+sodium sulfate and cesium chloride+sodium sulfate at 25°C have been measured. Interaction coefficients have been calculated and also the excess Gibbs energy of mixing. A correlation is found between the binary interaction coefficients and the Pauling cation radius of the alkali halide component.

Osmotic coefficients of aqueous solutions of calcium chloride and calcium perchlorate at 25.deg.

Osmotic coefficients of aqueous solutions of calcium chloride and calcium perchlorate at 25.deg.

Variation of osmotic coefficients of aqueous solutions of tetraalkylammonium halides with temperature. Thermal and solute effects on solvent hydrogen bonding

Variation of osmotic coefficients of aqueous solutions of tetraalkylammonium halides with temperature. Thermal and solute effects on solvent hydrogen bonding

Osmotic coefficients of aqueous solutions of tri-n-alkylsulfonium halides at 25.degree.

Osmotic coefficients of aqueous solutions of tri-n-alkylsulfonium halides at 25.degree.

Activity coefficients of some polyphosphates in aqueous solution

The osmotic coefficients of aqueous solutions of sodium tri- and pyrophosphates and potassium tri-, pyro- and trimetaphosphates have been determined at 25°C by an isopiestic method. Activity coefficients were derived by graphical integration of the Gibbs-Duhem equation after extrapolation of the osmotic data to infinite dilution by a Debye-Huckel-type of equation.

The osmotic activity and conductivity of aqueous solutions of some typical colloidal electrolytes

1. 1. The osmotic coefficients of aqueous solutions of 10 different anionic and cationic colloidal electrolytes have been measured by freezing point depression, now bringing the total number of those investigated to 64. Conductivities were also measured for these and two other materials too insoluble at 0°C. for freezing point determinations. 2. 2. The relative lowering of conductivity with increasing concentration is less than that of osmotic coefficient. In the case of polycyclic structures, such as a bile salt or sodium abietate, the latter measurement shows the presence of colloid with a critical concentration, whereas this does not appear in the conductivity curve. 3. 3. Addition of dimethyl phthalate, a substance insoluble in oil and water but solubilized by soap solutions, appears slightly to decrease colloid formation as reflected in osmotic coefficient and equivalent conductivity. 4. 4. The colloidal behavior of the laurate of several complex organic bases has been compared with that of potassium laurate. 5. 5. An ordinary molecule, sucrose, lowers the freezing point of water to the same extent as it lowers the freezing point of a solution of the colloidal electrolyte, potassium laurate.

The Activity and Osmotic Coefficients of Aqueous Solutions of Lanthanum Chloride at 25°

The Activity and Osmotic Coefficients of Aqueous Solutions of Lanthanum Chloride at 25°

The Activity and Osmotic Coefficients of Aqueous Solutions of Acetic Acid at the Freezing Point

The Activity and Osmotic Coefficients of Aqueous Solutions of Acetic Acid at the Freezing Point