Thermodynamics of transfer of benzoic acid from water to aqueous mixtures of urea and of some alcohols

1978 ◽  
Vol 82 (11) ◽  
pp. 1242-1245 ◽  
Author(s):  
Kaushik Das ◽  
Asim K. Das ◽  
Kumardev Bose ◽  
Kiron K. Kundu
Keyword(s):  
Benzoic Acid ◽  
Aqueous Mixtures ◽  
Thermodynamics Of Transfer

Temperature Dependent Solubility of Benzoic Acid in Aqueous Phase and Aqueous Mixtures of Aliphatic Alcohols

2020 ◽  
Vol 234 (11-12) ◽  
pp. 1771-1787
Author(s):  
Sayyar Muhammad ◽  
Sofia Sanam ◽  
Hamayun Khan ◽  
Akhtar Muhammad ◽  
Sabiha Sultana
Keyword(s):  
Benzoic Acid ◽  
Aqueous Phase ◽  
Linear Trend ◽  
Pure Water ◽  
Binary Solvents ◽  
Aqueous Mixtures ◽  
Analytical Technique ◽  
Temperature Range ◽  
Acid Solubility ◽  
Ethanol In Water

AbstractThe benzoic acid solubility in aqueous phase and in various aqueous mixtures of methanol, ethanol and 2-propanol was determined at temperatures ranging from 303 to 333 K by an analytical technique. The results showed that the solubility of the acid in alcohols-water binary mixtures is high as compared to pure aqueous phase. The addition of alcohols to water favors the dissolution of benzoic acid which increases further with the increase in alcohols content of water within the investigated temperature range. The benzoic acid solubility in water alone and aqueous mixtures of the selected alcohols was in the order of; 2-propanol in water > ethanol in water > methanol in water > pure water. It is also observed that within the investigated temperature range, the acid solubility increases with rise in temperature in both the aqueous phase and alcohols-water binary solvents. The logarithm of the mole fraction of the acid’s solubility also showed a linear trend against the temperature. The experimental results obtained in the current study were compared with the reported literature for the studied acid and other organic acids in various solvents and showing a good agreement. The study will have implications in the processes involving separation, crystallization and pharmaceutical formulation in various industries.

Thermodynamics of transfer of glycine, diglycine, and triglycine from water to aqueous solutions of urea, glycerol, and sodium nitrate

1988 ◽  
Vol 66 (3) ◽  
pp. 461-468 ◽  
Author(s):  
Himansu Talukdar ◽  
Sibaprasad Rudra ◽  
Kiron K. Kundu
Keyword(s):  
Sodium Nitrate ◽  
Regular Function ◽  
Scaled Particle Theory ◽  
Aqueous Mixtures ◽  
Free Energies ◽  
Thermodynamics Of Transfer ◽  
Different Temperatures ◽  
Composition Profiles ◽  
Cavity Effect ◽  
Nitrate Solutions

Standard free energies [Formula: see text] and entropies [Formula: see text] of transfer of glycine (G), diglycine (DG), and triglycine (TG), from water to aqueous mixtures of glycerol (GL) and urea (UH) have been determined from solubility measurements at different temperatures. This was also extended to an ionic cosolvent system like aqueous sodium nitrate solutions for G and DG. The observed [Formula: see text] and [Formula: see text]–composition profiles, as well as those obtained after correcting for the "cavity effect" as estimated by scaled particle theory (SPT), were examined in the light of various interactions. The corrected [Formula: see text]and [Formula: see text] values show a regular function of the peptide chain length of the amino acids and impart useful information regarding the involved relative structural effects of these ionic and non-ionic cosolvents.

Studies of the dissociation of 2,4,6-trinitrophenol in aqueous mixtures of methanol and ethanol at 25 °C

1985 ◽  
Vol 63 (11) ◽  
pp. 3129-3132 ◽  
Author(s):  
A. L. De ◽  
A. K. Atta
Keyword(s):  
Acetic Acid ◽  
Benzoic Acid ◽  
Solvent Effect ◽  
Spectrophotometric Method ◽  
Dissociation Constants ◽  
Dispersion Interaction ◽  
Organic Component ◽  
Aqueous Mixtures ◽  
Dispersion Interactions ◽  
The Difference

Thermodynamic dissociation constants (sK)m of 2,4,6-trinitrophenol have been determined at 25 °C in aqueous mixtures containing 30, 50, 70, and 90% by weight of methanol and 30, 50, 70, 90, and 95% by weight of ethanol by spectrophotometric method. Solvent effect on the dissociation of the acid: δ(ΔG0) = 2.303RT[p(sK)N − p(wK)N] shows an unusual behaviour, the value decreases and passes through a minimum and ultimately becomes positive as the proportion of organic component in the solvent is progressively increased. The results have been compared with those of other uncharged acids like acetic acid, benzoic acid available from literature. The difference of behaviour (minimum characteristic in δ(ΔG0) curve) has been attributed to very strong dispersion interaction of trinitrophenolate anion with the organic component of the solvent. The overall behaviour of this acid indicates that solvent effect is an involved process being guided by electrostatic and dispersion interactions besides relative solvent basicities.

Study of Benzoic Acid Solubility in Imidazolium Formate as Pure Ionic Liquid and Its Binary Aqueous Mixtures

2017 ◽  
Vol 68 (10) ◽  
pp. 2256-2260
Author(s):  
Claudia Simona Stefan ◽  
Elena Roxana Chiriac ◽  
Oana Dragostin ◽  
Elena Lacramioara Lisa ◽  
Maria Cioroi
Keyword(s):  
Ionic Liquid ◽  
Benzoic Acid ◽  
Organic Solvents ◽  
Mole Fraction ◽  
Salt Concentration ◽  
Salt Water ◽  
Water Mixture ◽  
Aqueous Mixtures ◽  
Acid Solubility ◽  
Aqueous Mixture

The determination of benzoic acid (BAc) solubility in pure imidazolium formate (ImForm) and their aqueous mixtures of [ImForm/water], was performed by the acid-base titration of the saturated solutions. [ImForm/water] solutions were tested using an ImForm concentration ranging from 1.66-4.33 g/L. The BAc solubility in pure ionic liquid was compared with that of some common organic solvents reported in literature, such as: ethanol, chloroform, cyclohexane. The highest solubility of BAc was for pure ImForm (from 1073 g/L at 293 K up to 2200 g/L at 323 K), the determined values being superior to BAc solubility in organic solvents mentioned. The results confirm that the polar solvents, such as ImForm and ethanol, present the highest BAc solubility values. At 293 K, the mole fraction of BAc in pure ImForm was 2.8 times higher than the mole fraction of BAc in ethanol. The BAc solubility in binary mixtures [ImForm/water] was compared with that determined in [NaCl/water] mixtures. At the same salt concentration, ranging from 1.66 to 4.33 g/L, at a constant working temperature (323 K), the increasing concentration of NaCl lowers the solubility of BAc. In opposite, the increasing of ImForm concentration determines a considerable increase in BAc solubility into the [ImForm/water] mixture. At 277 K, for 1.66 g/L salt concentration in water, the BAc solubility in [salt/water] solvents shows very similar values (~1.3 g/L) for both [ImForm/water] and [NaCl/water]. If the temperature increases to 323 K, the BAc solubility in [ImForm/water] mixture is about 1.5 times higher than that of solubility in distillated water and 2.5 times higher compared to that in [NaCl/water]. It was concluded that the benzoic acid presents a great solubility in pure ImForm and in its [ImForm/water] aqueous mixture.

Ion–ion–solvent interactions in aqueous ionic cosolvent systems. IV. Transfer energetics of water, p-nitroaniline, and benzoic acid from emf/solubility measurements at different temperatures in aqueous sodium nitrate solvent system

1988 ◽  
Vol 66 (3) ◽  
pp. 469-475
Author(s):  
Sibaprasad Rudra ◽  
Himansu Talukdar ◽  
Kiron K. Kundu
Keyword(s):  
Benzoic Acid ◽  
Sodium Nitrate ◽  
Solvent System ◽  
Aqueous Mixtures ◽  
Free Energies ◽  
Salting Out ◽  
Emf Measurements ◽  
Solvent Interactions ◽  
Different Temperatures ◽  
Composition Profiles

Autoionization constants (Ks) of aqueous mixtures of 1, 2, and 4 m sodium nitrate used as an ionic cosolvent system have been determined from emf measurements of the cell: Pt, H2 (g, 1 atm)/KOH (m1) KCl (m2), solvent/AgCl–Ag at five equidistant temperatures ranging from 15–35 °C. The standard free energies (ΔG0) and entropies (ΔS0) of autoionisation of the solvents were then evaluated from these data. Relative free energies (ΔG0) and entropies of (ΔS0)of autoionization of the solvents when coupled with the previously determined transfer free energies [Formula: see text] and entropies [Formula: see text] of H+ yielded [Formula: see text][Formula: see text],[Formula: see text] and [Formula: see text]. Values of [Formula: see text] and [Formula: see text] obtained after correcting for [Formula: see text], as well as [Formula: see text] and [Formula: see text]obtained after correcting the "cavity effect" and Born-type electrostatic effect suggests that while the "basicity" of the aqueous NaNO3 solutions decreases, the "acidity" more or less increases with NaNO3 concentration. The observed [Formula: see text]– and [Formula: see text]–composition profiles were also examined in the light of Kundu et al.'s four-step transfer process and the involved order–disorder phenomena, respectively, as proposed earlier.Standard free energies [Formula: see text] and entropies [Formula: see text] of transfer of p-nitroaniline (pNA) and benzoic acid (HBz) for the solvent system have also been determined from solubility measurements at different temperatures. The observed [Formula: see text]–and [Formula: see text]–composition profiles appear to reflect the salting-out effect of the salt and the [Formula: see text]–and [Formula: see text]–composition profiles confirm the applicability of either of these quantities rather than [Formula: see text], as a better structural probe both for aquo-ionic and aquo-organic solvents.

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