Polyol–Water interactions. Apparent molal heat capacities and volumes of aqueous polyol solutions

1977 ◽  
Vol 55 (22) ◽  
pp. 3825-3830 ◽  
Author(s):  
Giuseppa DiPaola ◽  
Bernard Belleau
Keyword(s):  
Aqueous Solutions ◽  
Infinite Dilution ◽  
Pure Water ◽  
Water Environment ◽  
Heat Capacities ◽  
Flow Microcalorimeter ◽  
Specific Heats ◽  
Structural Interactions ◽  
Apparent Molal Heat Capacities

Volumetric specific heats (25 °C) and densities (24 °C) were measured with a flow microcalorimeter and flow densimeter for 12 polyols in water (0.05 to 2 m), and for NaCl and n-Bu4NBr in 1 m aqueous alditol solutions. The infinite dilution properties [Formula: see text] of the polyols show specificities in polyol−water interactions which are discussed in terms of the compatibility of the polyol stereochemistry and the existing water environment. The derived heat; capacities and volumes of transfer of hydrophobic and hydrophilic probes to aqueous solutions of homologous polyols suggest that structural interactions are reduced in these systems as compared to pure water.

Apparent molal heat capacities and volumes of aqueous electrolytes at 25 °C: NaClO3, NaClO4, NaNO3, NaBrO3, NaIO3, KClO3, KBrO3, KIO3, NH4NO3, NH4Cl, and NH4ClO4

1978 ◽  
Vol 56 (1) ◽  
pp. 24-28 ◽  
Author(s):  
Alain Roux ◽  
Goolam M. Musbally ◽  
Gérald Perron ◽  
Jacques E. Desnoyers ◽  
Prem Paul Singh ◽  
...  
Keyword(s):  
Aqueous Solutions ◽  
Infinite Dilution ◽  
Heat Capacities ◽  
Aqueous Electrolytes ◽  
Apparent Molal Volumes ◽  
Hückel Theory ◽  
Standard Values ◽  
Molal Volumes ◽  
Apparent Molal Heat Capacities

Measurements at 25 °C with flow calorimeters and densimeters have led to heat capacities and densities of aqueous solutions of 11 1:1 electrolytes: NaClO3, NaBrO3, NaIO3, NaNO3, NaClO4, NH4NO3, KClO3, KBrO3, KIO3, NH4Cl, and NH4ClO4. The first 6 salts were studied up to near saturation. We have used results of these measurements to obtain apparent molal heat capacities and apparent molal volumes of the various solutes. Extrapolation to infinite dilution on the basis of the Debye–Hückel theory bas led to [Formula: see text]and [Formula: see text] values for each solute. We have compared these standard values with results of earlier investigations.

Apparent molal heat capacities and volumes of amino acids in aqueous polyol solutions

1978 ◽  
Vol 56 (13) ◽  
pp. 1827-1831 ◽  
Author(s):  
Giuseppa DiPaola ◽  
Bernard Belleau
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Aqueous Solutions ◽  
Transfer Functions ◽  
Heat Capacities ◽  
Side Chains ◽  
Dilute Solutions ◽  
Flow Microcalorimeter ◽  
Regular Increase ◽  
Apparent Molal Heat Capacities

Densities (24 °C) and volumetric specific beats (25 °C) were measured for amino acids (0.05–0.5 m) containing apolar side chains in water, and in aqueous solutions of glycerol, mannitol, sorbitol, NaCl, urea, and Gu•HCl, with a flow densimeter and flow microcalorimeter respectively.The derived apparent molal quantifies and transfer functions of the amino acids in aqueous polyol solutions reveal no specificities which might explain the origin of the unique behavior of polyols in protein systems. However, the study did reveal a regular increase in the structure-making ability of the amino acid as the hydrophobicity of the side chains increased. This structure-making tendency was reduced significantly in dilute solutions of the higher polyols.

Heat capacities of aqueous electrolytes: eight 1:1 electrolytes and ΔCp0 for ionization of water at 298 K

1976 ◽  
Vol 54 (21) ◽  
pp. 3315-3318 ◽  
Author(s):  
Prem Paul Singh ◽  
Earl M. Woolley ◽  
Keith G. McCurdy ◽  
Loren G. Hepler
Keyword(s):  
Aqueous Solutions ◽  
Infinite Dilution ◽  
Heat Capacities ◽  
Aqueous Electrolytes ◽  
Flow Calorimeter ◽  
Apparent Molal Heat Capacities ◽  
Ionization Of Water

We have made measurements with a flow calorimeter leading to apparent molal heat capacities of aqueous solutions of NaCl, HCl, KBr, KCl, KOH, NaBr, HBr, and NaOH at 298 K. Results have been used to derive apparent molal heat capacities of these electrolytes at infinite dilution and thence ΔCp0 = −215.2 ± 4 J K−1mol−1 for ionization of H2O(liq) at 298 K.

Apparent molar heat capacities and volumes of unsaturated heterocyclic solutes in aqueous solution at 25 °C

1980 ◽  
Vol 58 (7) ◽  
pp. 704-707 ◽  
Author(s):  
Octavian Enea ◽  
Carmel Jolicoeur ◽  
Loren G. Hepler
Keyword(s):  
Aqueous Solution ◽  
Aqueous Solutions ◽  
Heterocyclic Compounds ◽  
Infinite Dilution ◽  
Heat Capacities ◽  
Group Additivity ◽  
Standard State ◽  
Apparent Molar Heat Capacities ◽  
Partial Molar Heat Capacities

Measurements at 25 °C with flow calorimeters and densimeters have led to heat capacities and densities of aqueous solutions of 15 unsaturated heterocyclic compounds containing nitrogen. From the results of these measurements we have obtained apparent molar heat capacities and volumes of the solutes. Extrapolations to infinite dilution have led to corresponding standard state apparent and partial molar heat capacities and volumes, which have been analyzed in terms of atomic and group additivity relationships.

scholarly journals Polyol–protein interactions. Thermodynamical evidence for a selective solvation of glycerol and hexitols by aqueous β-lactoglobulin

1978 ◽  
Vol 56 (6) ◽  
pp. 848-850 ◽  
Author(s):  
Giuseppa DiPaola ◽  
Bernard Belleau
Keyword(s):  
Specific Heat ◽  
Protein Interactions ◽  
Heat Capacities ◽  
Structural Effects ◽  
Flow Microcalorimeter ◽  
Specific Heats ◽  
Selective Solvation ◽  
Apparent Specific Heat ◽  
Specific Heat Capacities ◽  
Β Lactoglobulin

Apparent specific heat capacities and volumes of the protein β-lactoglobulin have been determined under a variety of solute–solvent and solvent–cosolvent compositions. These quantities were derived from measurements of volumetric specific heats and densities with a flow microcalorimeter and flow densimeter. The effect of homologous polyols on the isothermal denaturation of the protein by urea at 25 °C was investigated. The results suggest that polyol binding on the protein is sensitive to structural effects, maximum discrimination being exerted in favor of glycerol and its doubles, the hexitols.

Heat capacities and volumes of dilute aqueous solutions of 1,3-dioxane and trioxane

1981 ◽  
Vol 59 (17) ◽  
pp. 2599-2600 ◽  
Author(s):  
Gérald Perron ◽  
Jacques E. Desnoyers
Keyword(s):  
Aqueous Solutions ◽  
Concentration Dependence ◽  
Infinite Dilution ◽  
Unit Volume ◽  
Heat Capacities ◽  
Cyclic Ethers ◽  
Group Additivity ◽  
Simple Correlation ◽  
Dilute Aqueous Solutions ◽  
Molal Volumes

The densities and heat capacities per unit volume of 1,3-dioxane and trioxane were measured in water at 25 °C in the concentration range 0.1 to 1 mol kg−1. Apparent molal volumes [Formula: see text] and [Formula: see text] heat capacities were derived. The infinite dilution [Formula: see text] shows excellent group additivity with other cyclic ethers in water but the additivity is less satisfactory for[Formula: see text]. No simple correlation can be made for the concentration dependence of these functions.

Apparent molar heat capacities and volumes of aqueous solutions of several 1:1 electrolytes at elevated temperatures

1986 ◽  
Vol 64 (5) ◽  
pp. 926-931 ◽  
Author(s):  
Preet P. S. Saluja ◽  
Jacques C. LeBlanc ◽  
Harold B. Hume
Keyword(s):  
Heat Capacity ◽  
Aqueous Solutions ◽  
Room Temperature ◽  
Elevated Temperatures ◽  
Constant Pressure ◽  
Solubility Limit ◽  
Heat Capacities ◽  
Apparent Molar Heat Capacities ◽  
Flow Microcalorimeter ◽  
Good Agreement

The results of heat capacity (Cp) and density (d) measurements at 0.6 MPa and in the temperature range 298.15–373.15 K are presented for several 1:1 electrolytes in water. The flow microcalorimeter and densimeter used for these measurements were modificatons of the room-temperature designs. Data were obtained over concentrations ranging from 0.02 to 1.0 mol kg−1 (or to the solubility limit, whichever was lower). The heat capacity of a solution relative to that of water was measured with a precision of ±0.1 mJ K−1 g−1 at all temperatures. The density of a solution relative to that of water was measured with a precision of ±5 μg cm−3. These Cp and d results were used to calculate the apparent molar heat capacities, [Formula: see text], and volumes, [Formula: see text], at 298.15, 323.15, 348.15, and 373.15 K, at a constant pressure of 0.6 MPa. These results are in good agreement with available literature data.

Heat capacities, volumes, and expansibilities of sodium phenyl carboxylates in water

1977 ◽  
Vol 55 (19) ◽  
pp. 3368-3370 ◽  
Author(s):  
Claude Ostiguy ◽  
Jagdish C. Ahluwalia ◽  
Gerald Perron ◽  
Jacques E. Desnoyers
Keyword(s):  
Unit Volume ◽  
Heat Capacities ◽  
Simple Explanation ◽  
Flow Microcalorimeter ◽  
Partial Molal Heat Capacities ◽  
Apparent Molal Heat Capacities

The heat capacities per unit volume at 25 °C and densities from 10 to 55 °C of sodium phenyl carboxylates were measured with a flow microcalorimeter and a flow densimeter. The apparent molal heat capacities and volumes were used to derive standard partial molal heat capacities [Formula: see text], volumes [Formula: see text], and expansibilities [Formula: see text]. The CH2 contribution to [Formula: see text] is the same as that usually observed for aliphatic solutes but the contribution to [Formula: see text] and [Formula: see text] is not constant and significantly different. No simple explanation can be offered for this anomaly.

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