Study of electrolytic solution process using the scaled-particle theory. 2. The standard entropy of solvation

1980 ◽  
Vol 102 (7) ◽  
pp. 2181-2188 ◽  
Author(s):  
Utpal Sen
Keyword(s):  
Solution Process ◽  
Scaled Particle Theory ◽  
Standard Entropy ◽  
Particle Theory ◽  
Electrolytic Solution

A study of the electrolytic solution process using the scaled particle theory. 5. Heat capacity of aqueous ions at elevated temperatures

1991 ◽  
Vol 69 (3) ◽  
pp. 440-450
Author(s):  
Utpal Sen
Keyword(s):  
Heat Capacity ◽  
Elevated Temperatures ◽  
Solution Process ◽  
Scaled Particle Theory ◽  
Thermodynamic Quantities ◽  
Particle Theory ◽  
Standard Heat ◽  
Born Model ◽  
Standard Heat Capacity ◽  
Aqueous Ions

A theory composite of the scaled particle theory and the Born model of solvent continuum has been used to theoretically calculate the standard heat capacity of hydration as well as the partial molal heat capacity of aqueous ions and electrolytes at elevated temperatures. The uncertainties in the second temperature derivatives of solvent dielectric constant at various temperatures present a barrier to an accurate heat capacity prediction by the theory. Nevertheless, the agreement between the predicted standard heat capacity of electrolytes in solution and the corresponding experimental data, particularly at higher temperatures, is encouraging. Moreover, the composite theory seems to provide the most accurate thermodynamic predictions to date for aqueous electrolytes at higher temperatures without involving any arbitrary adjustable parameter. We therefore use this theory to find the proper ionic scale of the partial molal heat capacities at elevated temperatures. Key words: scaled particle theory, solvent continuum model of Born, standard heat capacity of aqueous ions, absolute scale for hydration thermodynamic quantities.

Solubility of nonpolar gases in 2-methylcyclohexanone between 273.15 and 303.15 K at 101.32 kPa partial pressure of gas

1989 ◽  
Vol 67 (5) ◽  
pp. 809-811 ◽  
Author(s):  
Maria Asuncion Gallardo ◽  
Maria del Carmen Lopez ◽  
Jose Santiago Urieta ◽  
Celso Gutierrez Losa
Keyword(s):  
Partial Pressure ◽  
Thermodynamic Functions ◽  
Solution Process ◽  
Pair Potential ◽  
Scaled Particle Theory ◽  
Sphere Diameter ◽  
Gas Solubility ◽  
Particle Theory ◽  
Potential Parameters ◽  
Solubility Of Nonpolar Gases

Solubility measurements of several nonpolar gases (He, Ne, Ar, Kr, Xe, H2, D2, N2, CH4, C2H4, C2H6, CF4, SF6, and CO2) in 2-methylcyclohexanone at 273.15–303.15 K and a partial pressure of gas of 101.32 kPa are reported. Thermodynamic functions (Gibbs energy, enthalpy, and entropy) for the solution process at 298.15 K and 101.32 kPa partial pressure of gas are evaluated. Use is made of the Scaled Particle Theory applied to gas solubility for determining Lennard-Jones (6, 12) pair-potential parameters and temperature dependence of the effective hard-sphere diameter of the solvent. The values that this theory predicts for the solution thermodynamic functions are also calculated. Keywords: 2-methylcyclohexanone, gas solubility, thermodynamic functions of solution, Henry coefficient, scaled particle theory.

scholarly journals Use of scaled-particle theory in the assessment of the Ph4As+/Ph4B− assumption for single ions

1979 ◽  
Vol 57 (1) ◽  
pp. 71-76 ◽  
Author(s):  
Michael H. Abraham ◽  
Asadollah Nasehzadeh
Keyword(s):  
Free Energy ◽  
Recent Work ◽  
Scaled Particle Theory ◽  
Cavity Formation ◽  
Energy Term ◽  
Free Energies ◽  
Particle Theory ◽  
Novel Method ◽  
Energy Of Interaction ◽  
Solvent Molecules

A novel method for the assessment of the Ph4As+/Ph4B− assumption for free energies of transfer of single ions has recently been suggested by Treiner, and used by him to deduce that the assumption is not valid for transfers between water, propylene carbonate, sulpholane, dimethylsulphoxide, N-methyl-2-pyrrolidone, and perhaps also dimethylformamide. The basis of the method is the estimation of the free energy of cavity formation by scaled-particle theory, together with the hypothesis that the free energy of interaction of Ph4As+ (or Ph4B−) with solvent molecules is the same in all solvents, ΔGt0(int) = 0. It is shown in the present paper that (a) whether or not the Ph4As+/Ph4B− assumption applies to transfer to a given solvent depends on which other solvent is taken as the reference solvent in Treiner's method, (b) the calculation of the cavity free energy term by scaled-particle theory and by the theory of Sinanoglu – Reisse – Moura Ramos (SRMR) yields values so different that the method cannot be considered reliable, (c) the calculation of cavity enthalpies and entropies for Ph4As+ or Ph4B− by scaled-particle theory yields results that are chemically not reasonable, (d) the hypothesis that ΔGt0(int) = 0 conflicts with SRMR theory, and (e) the conclusions reached by Treiner are not in accord with recent work that in general supports the Ph4As+/Ph4B− assumption for solvents that are rejected by Treiner.

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