A new model for calculating the viscosity of aqueous solutions has been developed. Parameters for 74 solutes were established based on a critical review of the literature for solutions of one solute in water, with over 9000 points included. The average difference between the calculated and experimental viscosities is less than 0.1 %, and the standard deviation of this difference is 3.7 % of the average experimental viscosity. The model was validated by estimating published viscosity for systems of more than one solute in water. The average difference between experimental and calculated values for 1700 points is −2.7 %, and the standard deviation of this difference is 16 % of the average experimental viscosity. The median standard deviation of the difference between experimental and calculated values is 3.5 % of the experimental viscosity. The solutes studied are (NH4)2SO4, AlCl3, BaCl2, Ca(NO3)2, CaCl2, Cd(NO3)2, CdCl2, CdSO4, CoCl2, CoSO4, Cr2(SO4)3, CrCl3, Cu(NO3)2, CuCl2, CuSO4, Fe2(SO4)3, FeCl2, FeSO4...

Model for Calculating the Viscosity of Aqueous Solutions

A new model for calculating the density of aqueous solutions of electrolytes has been developed. Parameters for 59 electrolytes were established on the basis of an extensive critical review of the published literature for solutions of one electrolyte in water, with over 10 700 points included. The average difference between the calculated and experimental density of solutions of water and one electrolyte is 0.10 kg m-3 with a standard deviation of 1.44 kg m-3. The model was validated by predicting the density of systems of two or more electrolytes in water. The average difference between experimental and calculated values for over 1600 points is 0.003 kg m-3 with a standard deviation of 1.39 kg m-3. The electrolytes studied are AlCl3, Al2(SO4)3, BaCl2, CaCl2, CdCl2, CdSO4, CoCl2, CoSO4, CrCl3, Cr2(SO4)3, CuCl2, CuSO4, FeCl2, FeSO4, FeCl3, Fe2(SO4)3, HCl, HCN, HNO3, H3PO4, H2SO4, KCl, K2CO3, KNO3, KOH, K2SO4, LiCl, Li2SO4, MgCl2, MgSO4, MnCl2, MnSO4, NaBr, NaCl, NaClO3, Na2CO3, NaF, NaHCO3, NaH2PO4, Na2HPO...

Model for Calculating the Density of Aqueous Electrolyte Solutions

Steady state and time-resolved fluorescence spectroscopic techniques have been used to explore the Stokes’ shift dynamics and rotational relaxation of a dipolar solute probe in molten mixtures of acetamide (CH3CONH2) with sodium and potassium thiocyanates (Na /KSCN) at T ∼ 318 K and several other higher temperatures The dipolar solute probe employed for this study is coumarin 153 (C153) Six different fractions (f) of KSCN of the following ternary mixture composition, 075CH3CONH2 + 025[(1 − f)NaSCN + fKSCN], have been considered The estimated experimental dynamic Stokes’ shift for these systems ranges between 1800 and 2200 cm−1 (±250 cm−1), which is similar to what has been observed with the same solute probe in several imidazolium cation based room temperature ionic liquids (RTIL) and in pure amide solvents Interestingly, this range of estimated Stokes’ shift, even though not corresponding to the megavalue of static dielectric constant reported in the literature for a binary mixture of molten CH3CON

Fluorescence spectroscopic studies of (acetamide + sodium/potassium thiocyanates) molten mixtures: composition and temperature dependence.

Calculations of the size and density of atmospheric aerosols are complicated by the fact that they can exist at concentrations highly supersaturated with respect to dissolved salts and supercooled with respect to ice. Densities and apparent molar volumes of solutes in aqueous solutions containing the solutes H(2)SO(4), HNO(3), HCl, Na(2)SO(4), NaNO(3), NaCl, (NH(4))(2)SO(4), NH(4)NO(3), and NH(4)Cl have been critically evaluated and represented using fitted equations from 0 to 50 °C or greater and from infinite dilution to concentrations saturated or supersaturated with respect to the dissolved salts. Using extrapolated densities of high-temperature solutions and melts, the relationship between density and concentration is extended to the hypothetical pure liquid solutes. Above a given reference concentration of a few mol kg(-1), it is observed that density increases almost linearly with decreasing temperature, and comparisons with available data below 0 °C suggest that the fitted equations for density can be extrapolated to very low temperatures. As concentration is decreased below the reference concentration, the variation of density with temperature tends to that of water (which decreases as temperature is reduced below 3.98 °C). In this region below the reference concentration, and below 0 °C, densities are calculated using extrapolated apparent molar volumes which are constrained to agree at the reference concentrations with an equation for the directly fitted density. Calculated volume properties agree well with available data at low temperatures, for both concentrated and dilute solutions. Comparisons are made with literature data for temperatures of maximum density. Apparent molar volumes at infinite dilution are consistent, on a single ion basis, to better than ±0.1 cm(3) mol(-1) from 0 to 50 °C. Volume properties of aqueous NaHSO(4), NaOH, and NH(3) have also been evaluated, at 25 °C only. In part 2 of this work (ref 1 ) an ion interaction (Pitzer) model has been used to calculate apparent molar volumes of H(2)SO(4) in 0-3 mol kg(-1) aqueous solutions of the pure acid and to represent directly the effect of the HSO(4)(-) ↔ H(+) + SO(4)(2-) reaction. The results are incorporated into the treatment of aqueous H(2)SO(4) density described here. Densities and apparent molar volumes from -20 to 50 °C, and from 0 to 100 wt % of solute, are tabulated for the electrolytes listed in the title and have also been incorporated into the extended aerosol inorganics model (E-AIM, http://www.aim.env.uea.ac.uk/aim/aim.php) together with densities of the solid salts and hydrates.

Densities and Apparent Molar Volumes of Atmospherically Important Electrolyte Solutions. 1. The Solutes H2SO4, HNO3, HCl, Na2SO4, NaNO3, NaCl, (NH4)2SO4, NH4NO3, and NH4Cl from 0 to 50 °C, Including Extrapolations to Very Low Temperature and to the Pure Liquid State, and NaHSO4, NaOH, and NH3 at 25 °C

A model for calculating the heat capacity of complex aqueous solutions with an arbitrary number of solutes and at an arbitrary temperature was developed. Parameters for 79 solutes were established based on a critical review of the literature for solutions of one solute in water, with about 6600 points included. The average difference between the calculated and experimental heat capacity is −0.0003 kJ·kg−1·K−1 with a standard deviation of 0.010 kJ·kg−1·K−1. The model was validated by comparing published and calculated heat capacities for 13 systems of more than one solute in water, with a total of 485 data points. The average difference between experimental and calculated values is −0.003 kJ·kg−1·K−1 with a standard deviation of 0.029 kJ·kg−1·K−1. Data are presented on the following 109 solutes, including data on density (16 300 points) and viscosity (10 700 points): (NH4)2SO4, Al2(SO4)3, AlCl3, Ba(NO3)2, BaCl2, Ca(CH3CO2)2, Ca(NO3)2, CaCl2, CaSO4, Cd(NO3)2, CdCl2, CdSO4, CH3CH2OH, CO2, CoCl2, CoSO4, Cr2(S...

A Model for Calculating the Heat Capacity of Aqueous Solutions, with Updated Density and Viscosity Data

The liquid-solid equilibrium temperatures of organic binary mixtures are treated in order to have the excess chemical potential. This thermodynamic quantity is statistically treated following the groups interaction theory and the interchange parametres are derivated.

Statistical Treatment of Data of Excess Chemical Potential of Organic Binary Mixtures

Apparent molal volumes of alkali metal nitrates at 30.deg.

This paper presents a final discussion on studies of solutions of electrolytes in molten acetamide. These studies deal with cryoscopic and ultrasonic (by shear waves) techniques and reveal the complexity of the behaviour of these systems due to strong ion-solvent interactions.

Supercooling phenomena in the binary systems: Acetamide-electrolytes

We report experimental data concerning the solid–liquid and liquid–liquid equilibrium temperatures for some binary systems composed of ethyl hexadecanoate and some bicarboxylic aliphatic acids. The crystallization curves of these systems and of others, previously published only in a graphical form, are used in order to obtain the excess chemical potential of the bicarboxylic acid along its crystallization curve. This thermodynamic quantity is compared with that calculated from the theory of group interaction, by means of the areas of the contact surfaces and of three interchange energy parameters.

Le potentiel chimique d'excès dans des systèmes binaires: acides dicarboxyliques –acides monocarboxyliques ou esters. L'énergie libre d'interéchange entre groupes aliphatiques et carboxyliques

Maria A. Berchiesi

Papers

Statistical Treatment of Data of Excess Chemical Potential of Organic Binary Mixtures

Apparent molal volumes of alkali metal nitrates at 30.deg.

Supercooling phenomena in the binary systems: Acetamide-electrolytes

Le potentiel chimique d'excès dans des systèmes binaires: acides dicarboxyliques –acides monocarboxyliques ou esters. L'énergie libre d'interéchange entre groupes aliphatiques et carboxyliques

Liquid-solid equilibriums in the Na+-HCOO-, -CNS-, -NO3- ternary system