Volumetric Properties Of Aqueous Solutions Research Articles

A Simple 1–1 Electrolyte: Volumetric Properties of Aqueous Solutions of Sulfuric Acid at Elevated Temperatures

Densities of aqueous solutions of sulfuric acid (H2SO4) have been measured by vibrating tube densimetry at molalities m varying from 0.02 to 3.0 mol·kg–1, at temperatures over the range 323.15 ≤ T/K ≤ 523.15 at 10 MPa pressure. These results were used to calculate the corresponding apparent molar volumes Vϕ(H2SO4,aq) and appear to be the first-ever systematic study of the volumetric properties of this important acid at elevated temperatures. At T ≤ 373.15 K, the present results aligned well with recent literature data and with values reported in the 1926 International Critical Tables. No reliable experimental data were found for comparison at higher temperatures. The present results confirm that at lower concentrations and temperatures, sulfuric acid solutions exist as a variable mixture of H+(aq) + HSO4–(aq) + SO42–(aq). However, at higher temperatures, the degree of association increases markedly such that at T ≥ 448.15 K, sulfuric acid solutions behave like a simple 1:1 electrolyte [H+(aq) + HSO4–(aq)] even at low concentrations. The variation of Vϕ(H2SO4,aq) over the entire experimental region was well modelled using a simple Pitzer equation that specifically included (where appropriate) the effects of chemical speciation. Combination of this model with relevant literature data enabled estimation of the standard ionic volume V°(HSO4–,aq) and the standard volume change ΔrV° for the reaction H+(aq) + SO42–(aq) → HSO4–(aq) at temperatures up to 523 K.

Volumetric Properties of aqueous solutions of Arabinose, Xylose and Galactose in presence / absence of Sodium Cyclamate

Sugars can affect our blood glucose (sugar), weight and blood fats. Synthetic sugars (artificial sweetener) provide little or no calories or carbohydrate or do not increase blood sugar. In food and pharmaceutical industries, blends of sweeteners are commonly used to design the food products and pharmaceutical doses, the information regarding type and extent of sweetener-sweetener and sweetener -water interactions and taste quality of the solution required. The aqueous solutions of arabinose, xylose and galactose with and without cyclamate are studied. Densities of solutions of arabinose, xylose and galactose in presence of 0.05, 0.15 and 0.3 m sodium cyclamate have been measured at 298.15K. Partial molar volumes, apparent specific volumes, partial molar volumes of transfer and doublet and triplet interaction parameters have been calculated. The information obtained from these parameters has been used to understand type and extent of sweetener-sweetener and sweetener -water interactions and taste quality of the solution.

Volumetric properties of disodium dihydrogen pyrophosphate aqueous solution from 283.15 to 363.15 K at 101.325 kPa

The purpose of this exploration was to determine the density and volumetric properties of the aqueous solution of Na2H2P2O7 with the molality varied from 0.08706 to 0.88402 mol·kg−1 measured at temperature intervals of 5 K from 283.15 to 363.15 K at 101.325 kPa using Anton Paar Digital vibrating-tube densimeter. The thermal expansion coefficient (α), apparent molar volume (VΦ), expansibility (ϕE), and partial molar volume (VB) of Na2H2P2O7 (aq) against temperature and molality have been evaluated from density data. On the basis of Pitzer ion-interaction apparent molar volume theory, the Pitzer single-salt parameters (βM,X0v, βM,X1v, βM,X2v and CM,Xv, MX = Na2H2P2O7), and their correlation coefficients ai of the temperature-dependence formula f (i, p, T) = a1 + a2ln(T/298.15) + a3(T − 298.15) + a4/(620 – T) + a5/(T − 227) for Na2H2P2O7 were obtained for the first time. It was revealed that predicted apparent molar volumes agreed well with the experimental values indicating the single salt parameters and the temperature-dependent formula are reliable.

Volumetric Properties of Aqueous Solutions of Zinc Sulfate at Temperatures from 298.15 to 393.15 K and Pressures up to 10 MPa

Densities of aqueous solutions of zinc sulfate at molalities ranging from 0.1 to 3.0 mol·kg–1 were measured with a commercial vibrating tube densimeter at temperatures from 298.15 to 393.15 K and a...

A Volumetric Pitzer Model for Aqueous Solutions of Zinc Sulfate up to Near-Saturation Concentrations at Temperatures from 293.15 to 393.15 K and Pressures up to 10 MPa

Literature data for the volumetric properties of aqueous solutions of zinc sulfate have been compiled and compared with extensive recently available measurements. A semi-empirical Pitzer model has ...

Volumetric Properties of Aqueous Solutions of Acetamide in the 274.15–333.15 K Range of Temperatures

The densities of aqueous solutions of acetamide up to a mole fraction of x2 = 0.3875 are measured over a wide range of temperatures (274.15–333.15) K at atmospheric pressure. The partial molar volumes of water and acetamide, the partial molar isobaric expansivities of the components, and the limiting partial properties of acetamide in water are calculated. The shift in the temperature of the maximum density of water at low temperatures is calculated. The results are discussed in terms of solute–solvent and solute–solute interactions.

Temperature Effect on the Adsorption and Volumetric Properties of Aqueous Solutions of Kolliphor®ELP.

Density, viscosity and surface tension of Kolliphor® ELP, the nonionic surfactant aqueous solutions were measured at temperature T = 293–318 K and at 5K interval. Steady-state fluorescence measurements have been also made using pyrene as a probe. On the basis of the obtained results, a number of thermodynamic, thermo-acoustic and anharmonic parameters of the studied surfactant have been evaluated and interpreted in terms of structural effects and solute–solvent interactions. The results suggest that the molecules of studied surfactant at concentrations higher than the critical micelle concentration act as structure makers of the water structure.

Comment on “Volumetric properties of aqueous solution of lithium tetraborate from 283.15 to 363.15 K at 101.325 kPa” [J. Chem. Thermodyn. 120 (2018) 151–156] and its Corrigendum [J. Chem. Thermodyn. 123 (2018) 195–197

Inconsistencies in the apparent molar volume values for aqueous lithium tetraborate solutions reported by Guo and co-workers are exacerbated in the Corrigendum by Cao and co-workers. At 363 K the discrepancies relative to the corrected values in this work exceed 20 cm3 mol−1 and 100 cm3 mol−1 near 0.01 mol kg−1 for Guo et al. and Cao et al., respectively.

Corrigendum to the “Volumetric properties of aqueous solution of lithium tetraborate from 283.15 to 363.15 K at 101.325 kPa” [J. Chem. Thermodyn. 120 (2018) 151–156

Abstract Errors are discovered in the authors’ computed the apparent molar volume from the reported density of aqueous solutions of lithium tetraborate based on the equation. All the apparent molar volumes presented in Table 3 of the published paper by Guo and co-workers are in error. When the composition of Li 2 B 4 O 7 is high, the difference between our calculated V ϕ values and those reported by Guo is small. However, large difference is found with low compositions of Li 2 B 4 O 7 in solutions.

Volumetric properties of aqueous solution of lithium tetraborate from 283.15 to 363.15 K at 101.325 kPa

Abstract Densities of aqueous solutions of lithium tetraborate in the (0.01 to 0.12) mol·kg−1 concentration range at a 5 K intervals from 283.15 K to 363.15 K and 101.325 kPa were measured using a precise Anton Paar Digital vibrating-tube densimeter. Apparent molar volumes are obtained on the basis of experimental density data, and then the 3D diagram of (mi, T, Vϕ) apparent molar volumes against temperature and molality were plotted. On the basis of Pitzer ion-interaction equation of the apparent molar volume model, the Pitzer single-salt parameters ( β M,X ( 0 ) v , β M,X ( 1 ) v ), β M,X ( 2 ) v and C M,X ( v ) ), and their temperature-dependence correlation F(i, p, T) = a1 + a2T + a3T2 + a4/T + a5ln(T) + a6/(T−263) + a7/(680−T) (where T is temperature in Kelvin, p is a pressure in 101.325 kPa, ai are model parameters) for Li2B4O7 are obtained, which is not reported in the literature. The deviations of the experimental and calculated values of Pitzer single-salt parameters β M,X ( 0 ) v , β M,X ( 1 ) v , β M,X ( 2 ) v and C M,X ( v ) for Li2B4O7 are all within ±0.1, and those results indicate that the single salt parameters and their relational coefficients of temperature-dependence for Li2B4O7 obtained in this work are reliable.

Densities and Volumetric Properties of Aqueous Solutions of {Water (1) + N-Methylurea (2)} Mixtures at Temperatures of 274.15–333.15 K and at Pressures up to 100 MPa

Densities of the mixture {water (1) + N- methylurea (2)} in the concentration range to mole fraction x2 = 0.07071 (or to the solution molality concentration m2 = 4.22335 mol·kg–1) at atmospheric pressure in the temperature range from 274.15 to 333.15 K and compression k = ΔV/V0 at pressures to 100 MPa (10, 25, 50, 75, and 100) in the temperature range from 278.15 to 323.15 K (278.15, 288.15, 288.15, 308.15, 323.15) in the same concentration range were calculated in this study. The apparent molar volumes of N-methylurea Vϕ,2 and the partial molar volumes of both components V̅1 and V̅2 in the mixture, molar isothermal compressibilities KT,m, molar isobaric thermal expansions EP,m, and isochoric coefficients of thermal pressure β of the mixture were calculated. Moreover, volumetric measures for the infinitely dilute solution of N-methylurea solution were calculated: limiting partial molar volumes V̅2∞, the limiting partial molar isothermal compressibilities K̅T,2∞, and the limiting partial molar isobaric thermal expansions E̅P,2∞. The results obtained are discussed from the point of view of solute–solvent and solute–solute interactions.

Experimental and prediction of volumetric properties of aqueous solution of (allyltriphenylPhosphonium bromide—Triethylene glycol) deep eutectic solvents

Deep eutectic solvents (DESs) are derived from two or more salts as the hydrogen bond acceptors (HBAs) and hydrogen bond donors (HBDs). In this work, DES namely allyltriphenylphosphonium bromide- triethylene glycol (ATPPB-TEG) was prepared by using three molar ratios; i.e.,1:4, 1:10, and 1:16 of salt to HBDs. The volumetric properties of aqueous mixture of DESs, such as density, molar volume, isobaric thermal expansion, apparent molar volume and apparent molar expansibility were reported at several temperatures from 293.15 to 343.15K. A mathematical equation, namely Jouyban–Acree model (JAM), was used to correlate the experimental density and molar volume data. Furthermore, in order to calculate the limiting apparent molar volume values, the apparent molar volume values were fitted into a Redlich–Mayer equation. By applying Hepler equation, it was found that DESs 1:4 and 1:10 are as structure-maker solutes, while DES 1:16 is a structure-breaking solute in aqueous solutions.

Volumetric properties of aqueous solution of [C3mim][Ac] and [C4mim][Ac] from 283.15 to 323.15 K

The densities of 1-alkyl-3-methylimidazolium acetate [C3mim][Ac] and [C4mim][Ac] aqueous solution were measured in the concentration from 0.05000 to 3.000mol·kg−1 over the temperatures range from 283.15 to 323.15K. The coefficient of thermal expansion of the solution, α, apparent molar volume, ϕVB, the apparent molar expansibility of the solute, ϕE and the partial molar volume were calculated. The Pitzer's model was used to establish an equation to describe the volumetric properties and the corresponding parameters βMX(0)V, βMX(1)Vand CMXV were obtained. Comparing the values of VB0obtained by Pitzer's method with those values of Vϕ0calculated by Redlich and Meyer's shows that Pitzer's formulism can be applied in the aqueous solution of ionic liquids.

Volumetric properties of aqueous solutions of malonic acid

Densities of aqueous solutions of malonic acid in the (0.01–1.0) mole·kg−1 concentration range were measured at 5K intervals, from 278.15K to 343.15K. These densities served to determine the apparent molar volumes. Changes of densities with temperature permitted evaluation of the cubic expansion coefficients and the derivatives of isobaric heat capacities with respect to pressure which are interrelated with the second derivatives of volume with respect to temperature. Thermal dependence of volumetric properties of aqueous solutions of malonic acid is examined in terms of changes in the structure of water.

Volumetric properties of aqueous solutions with citrate ions – Trilithium citrate and triammonium citrate

Densities of aqueous solutions of trilithium citrate <1.74mol⋅kg−1 and triammonium citrate <0.20mol⋅kg−1, were measured at 5K intervals, from 278.15K to 343.15K. These densities served to determine the apparent molar volumes, the cubic expansion coefficients and the second derivatives of volume with respect to temperature which are interrelated with the derivatives of isobaric heat capacities with respect to pressure. Changes in the volumetric properties as a function of temperature and concentration of both citrates are discussed in terms of changes in the structure of water.

Volumetric properties of aqueous solutions of aluminium-l-lactate

Densities of aqueous solutions of aluminium-l-lactate <0.72mol·kg−1, were measured at T=5K intervals, from T=(278.15 to 343.15)K. These densities served to determine the apparent molar volumes, the cubic expansion coefficients and the second derivatives of volume with respect to temperature which are interrelated with the derivatives of isobaric heat capacities with respect to pressure. Changes in the volumetric properties as a function of temperature and concentration of aluminium-l-lactate, are discussed in terms of changes in the structure of water.

Density and Volumetric Properties of Aqueous Solutions of Trimethylamine N-Oxide in the Temperature Range from (278.15 to 323.15) K and at Pressures up to 100 MPa

Densities of aqueous solutions of trimethylamine N-oxide (TMAO) were measured over the concentration range (0.0875 to 4.3251) mol·kg–1 at temperatures (278.15, 288.15, 298.15, 308.15, and 323.15) K and pressures (0.101, 10, 25, 50, 75, and 100) MPa. Volumetric properties such as apparent molar volume of TMAO, Vϕ,2, molar isothermal compression, KT,m, molar isobaric expansion, EP,m, and internal pressure, Pint, of its aqueous solutions were calculated depending on concentration, temperature, and pressure. The volumetric partial properties of TMAO at infinite dilution in water (V2∞, KT,2∞, and EP,2∞) were also determined. The results were discussed from the standpoint of solute–solute and solute–solvent interactions.

Determination of Volume Properties of Aqueous Vanadyl Sulfate at 283.15 to 323.15 K

This paper reports the densities of aqueous VOSO4 that were measured by an Anton Paar DMA 4500 M from 0.0500 mol·kg–1 to 3.000 mol·kg–1 at 283.15 to 323.15 K. The apparent molar volume, ϕVB, the partial molar volume of VOSO4, V̅B, the apparent molar expansibility of the solute, ϕE, and coefficient of thermal expansion of the solution, α, were calculated. First, these properties described above have been discussed with the temperature and concentration variation. Then the values of the apparent molar volume, ϕVB, were fitted to Pitzer’s model for volumetric properties by the method of the least squares, which allowed the partial molar volume of the VOSO4 at infinite dilution, V̅B0, and Pitzer’s parameters, βMX(0)V, βMX(1)V, and CMXV, to be obtained. The small standard deviations of the fitting show that Pitzer’s model is also appropriate for representing the volumetric properties of aqueous solutions of VOSO4. Using the data from literature, the partial molar volume of the ion VO2+ at infinite dilution, V̅C0, was discussed and the result showed that the negative value of V̅C0 can be attributed to strong hydration of VO2+ as other divalent ions.

Acoustic and volumetric properties of aqueous solution of levofloxacin nickel complexes at 308K

The density and ultrasonic velocity were measured for aqueous solutions of nickel complex and its ternary complex with 1,10phenanthroline at 308 K. Using the experimental data, adiabatic compressibility , acoustic impedance , intermolecular free length and hydration number , apparent molar volume , limiting apparent molar volume , apparent molar compressibility , limiting apparent molar compressibility and their associated constants were calculated. These parameters were used to study the ion-solvent interaction in each solution.

Volumetric Properties of Aqueous Solutions of Ethylene Glycols in the Temperature Range of 293.15–318.15 K

Densities of aqueous solutions of Ethylene glycol (EG), diethylene glycol (DEG), and triethylene glycol (TEG) were measured at temperatures from 293.15 to 318.15 K and molalities ranging from 0.0488 to 0.5288 mol·kg−1. Volumes of all investigated solutions at a definite temperature were linearly dependent on the solute molality; from this dependence the partial molar volumes at infinite dilution were determined for all solutes. It was found that the partial molar volumes at infinite dilution V-2,0 were concentration independent and slightly increase with increasing temperature. The partial molar volumes at infinite dilution V-2,0 or the limiting apparent molar volumes of ethylene glycols were fitted to a linear equation with the number of oxyethylene groups (n) in the solute molecule. From this equation a constant contribution of the terminal (OH) and the (CH2CH2O) groups to the volumetric properties was obtained. The thermal expansion coefficient (α1,2) for all investigated solutions was calculated at temperatures from 293.15 to 318.15 K. The thermal expansion coefficients for all solutes increase with increasing temperature and molality. Values of (α1,2) were higher than the value of the thermal expansion coefficient of the pure water.