Comment on “The Gibbs free energy of cavity formation in a diverse set of solvents”[J. Chem. Phys. 153, 134501 (2020)]

Building on the previous chapter, this chapter examines gas phase chemical equilibrium, and the equilibrium constant. This chapter takes a rigorous, yet very clear, ‘first principles’ approach, expressing the total Gibbs free energy of a reaction mixture at any time as the sum of the instantaneous Gibbs free energies of each component, as expressed in terms of the extent-of-reaction. The equilibrium reaction mixture is then defined as the point at which the total system Gibbs free energy is a minimum, from which concepts such as the equilibrium constant emerge. The chapter also explores the temperature dependence of equilibrium, this being one example of Le Chatelier’s principle. Finally, the chapter links thermodynamics to chemical kinetics by showing how the equilibrium constant is the ratio of the forward and backward rate constants. We also introduce the Arrhenius equation, closing with a discussion of the overall effect of temperature on chemical equilibrium.

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Specific heat at constant pressure, enthalpy and Gibbs free energy of boron nitride (BN) using q-deformed exponential-type potential

Physica B Condensed Matter ◽

10.1016/j.physb.2021.412940 ◽

2021 ◽

Vol 613 ◽

pp. 412940 ◽

Cited By ~ 1

Author(s):

M. Habibinejad ◽

R. Khordad ◽

A. Ghanbari

Keyword(s):

Free Energy ◽

Boron Nitride ◽

Specific Heat ◽

Gibbs Free Energy ◽

Exponential Type ◽

Constant Pressure ◽

Type Potential

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Extended Gibbs Free Energy and Laplace Pressure of Ordered Hexagonal Close-Packed Spherical Particles: A Wettability Study

Langmuir ◽

10.1021/acs.langmuir.1c00343 ◽

2021 ◽

Author(s):

Amir Bayat ◽

Mahdi Ebrahimi ◽

Saeed Rahemi Ardekani ◽

Esmaiel Saievar Iranizad ◽

Alireza Zaker Moshfegh

Keyword(s):

Free Energy ◽

Gibbs Free Energy ◽

Laplace Pressure ◽

Spherical Particles ◽

Hexagonal Close Packed

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First-Principles Study of Mechanical and Thermodynamic Properties of Binary and Ternary CoX (X = W and Mo) Intermetallic Compounds

Materials ◽

10.3390/ma14061404 ◽

2021 ◽

Vol 14 (6) ◽

pp. 1404

Author(s):

Yunfei Yang ◽

Changhao Wang ◽

Junhao Sun ◽

Shilei Li ◽

Wei Liu ◽

...

Keyword(s):

Free Energy ◽

Thermodynamic Properties ◽

Gibbs Free Energy ◽

Density Functional ◽

Vibrational Entropy ◽

Functional Theory ◽

Lattice Constants ◽

The Density Functional Theory ◽

Ductile Behavior ◽

Pseudo Potential

In this study, the structural, elastic, and thermodynamic properties of DO19 and L12 structured Co3X (X = W, Mo or both W and Mo) and μ structured Co7X6 were investigated using the density functional theory implemented in the pseudo-potential plane wave. The obtained lattice constants were observed to be in good agreement with the available experimental data. With respect to the calculated mechanical properties and Poisson’s ratio, the DO19-Co3X, L12-Co3X, and μ-Co7X6 compounds were noted to be mechanically stable and possessed an optimal ductile behavior; however, L12-Co3X exhibited higher strength and brittleness than DO19-Co3X. Moreover, the quasi-harmonic Debye–Grüneisen approach was confirmed to be valid in describing the temperature-dependent thermodynamic properties of the Co3X and Co7X6 compounds, including heat capacity, vibrational entropy, and Gibbs free energy. Based on the calculated Gibbs free energy of DO19-Co3X and L12-Co7X6, the phase transformation temperatures for DO19-Co3X to L12-Co7X6 were determined and obtained values were noted to match well with the experiment results.

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Kinetics and thermodynamic properties related to the drying of 'Cabacinha' pepper fruits

Revista Brasileira de Engenharia Agrícola e Ambiental ◽

10.1590/1807-1929/agriambi.v20n2p174-180 ◽

2016 ◽

Vol 20 (2) ◽

pp. 174-180 ◽

Cited By ~ 8

Author(s):

Hellismar W. da Silva ◽

Renato S. Rodovalho ◽

Marya F. Velasco ◽

Camila F. Silva ◽

Luís S. R. Vale

Keyword(s):

Experimental Data ◽

Activation Energy ◽

Free Energy ◽

Thermodynamic Properties ◽

Gibbs Free Energy ◽

Removal Rate ◽

Effective Diffusion ◽

Drying Time ◽

Three Samples ◽

Different Temperatures

ABSTRACT The objective of this study was to determine and model the drying kinetics of 'Cabacinha' pepper fruits at different temperatures of the drying air, as well as obtain the thermodynamic properties involved in the drying process of the product. Drying was carried out under controlled conductions of temperature (60, 70, 80, 90 and 100 °C) using three samples of 130 g of fruit, which were weighed periodically until constant mass. The experimental data were adjusted to different mathematical models often used in the representation of fruit drying. Effective diffusion coefficients, calculated from the mathematical model of liquid diffusion, were used to obtain activation energy, enthalpy, entropy and Gibbs free energy. The Midilli model showed the best fit to the experimental data of drying of 'Cabacinha' pepper fruits. The increase in drying temperature promoted an increase in water removal rate, effective diffusion coefficient and Gibbs free energy, besides a reduction in fruit drying time and in the values of entropy and enthalpy. The activation energy for the drying of pepper fruits was 36.09 kJ mol-1.

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

Canadian Journal of Chemistry ◽

10.1139/v79-012 ◽

1979 ◽

Vol 57 (1) ◽

pp. 71-76 ◽

Cited By ~ 10

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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