Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Internal Gibbs free

The chemical potential p, of the adsorbate may be defined, following standard practice, in terms of the Gibbs free energy, the Helmholtz energy, or the internal energy (C/,). Adopting the last of these, we may write... [Pg.16]

Themodynamic State Functions In thermodynamics, the state functions include the internal energy, U enthalpy, H and Helmholtz and Gibbs free energies, A and G, respectively, defined as follows ... [Pg.444]

Ebox = total calculated energy inside the box drawn around the interface. This should be the Gibbs free energy. An approximation to it would be the internal energy atT=OK. [Pg.340]

Geometric mean approximation, 29 Germane barrier of internal rotation, 391 Gibbs, free energy, 30 function, 20... [Pg.406]

In most applications, thermodynamics is concerned with five fundamental properties of matter volume (V), pressure (/ ), temperature (T), internal energy (U) and entropy (5). In addition, three derived properties that are combinations of the fundamental properties are commonly encountered. The derived properties are enthalpy (//). Helmholtz free energy (A) and Gibbs free energy ) ... [Pg.8]

Table A4.6 gives the internal rotation contributions to the heat capacity, enthalpy and Gibbs free energy as a function of the rotational barrier V. It is convenient to tabulate the contributions in terms of VjRTagainst 1/rf, where f is the partition function for free rotation [see equation (10.141)]. For details of the calculation, see Section 10.7c. Table A4.6 gives the internal rotation contributions to the heat capacity, enthalpy and Gibbs free energy as a function of the rotational barrier V. It is convenient to tabulate the contributions in terms of VjRTagainst 1/rf, where f is the partition function for free rotation [see equation (10.141)]. For details of the calculation, see Section 10.7c.
The Gibbs free energy G and the chemical potentials include contributions from the internal energy, vibrational free energy, and configurational entropy. Since most relevant stmctures will have a low surface free energy, we obtain from (5.4) that... [Pg.133]

The quantity of primary interest in our thermodynamic construction is the partial molar Gibbs free energy or chemical potential of the solute in solution. This chemical potential reflects the conformational degrees of freedom of the solute and the solution conditions (temperature, pressure, and solvent composition) and provides the driving force for solute conformational transitions in solution. For a simple solute with no internal structure (i.e., no intramolecular degrees of freedom), this chemical potential can be expressed as... [Pg.309]

Whether a reaction is spontaneous or not depends on thermodynamics. The cocktail of chemicals and the variety of chemical reactions possible depend on the local environmental conditions temperature, pressure, phase, composition and electrochemical potential. A unified description of all of these conditions of state is provided by thermodynamics and a property called the Gibbs free energy, G. Allowing for the influx of chemicals into the reaction system defines an open system with a change in the internal energy dt/ given by ... [Pg.227]

The signal generated by the complex is governed by several physical phenomena associated with the matrix thickness. As soon as the probe is placed in contact with the analyte, external mass transfer controls the movement of the analyte toward the surface of the optical probe.(S4) The osmotic pressure and Gibbs free energy dictate the permeation of the analyte into the matrix. Once the analyte has penetrated the matrix, internal mass transfer resistance controls the movement of the analyte in the matrix. Eventually, the probe reaches a steady state of equilibrium with molecules continuously moving in and out of the matrix. [Pg.200]

Thermodynamic properties for explosion calculations are presented for major organic chemical compounds. The thermodynamic properties include enthalpy of formation, Gibbs free energy of formation, internal energy of formation and Helmholtz free energy of formation. The major chemicals include hydrocarbon, oxygen, nitrogen, sulfur, fluorine, chlorine, bromine, iodine and other compound types. [Pg.174]

Gibbs free energy of formation Internal energy of formation Helmholtz free energy of formation... [Pg.208]

The chemical potential of species i, is expressed in terms of the Gibbs free energy added to a system at constant T and P, as well as relative to the mole fraction of each added increment of i. When adding an incremental number of molecules of i, free energy is introduced in the form of internal energies of i as well as by the... [Pg.30]

Figure 6.2 Gibbs free energy of mixing in the quasi-chemical model of Toop and Samis (1962a,b), compared with values experimentally observed in Pb0-Si02 and Ca0-Si02 melts. Reprinted from Toop and Samis (1962b), with kind permission of ASM International, Materials Park, Ohio. Figure 6.2 Gibbs free energy of mixing in the quasi-chemical model of Toop and Samis (1962a,b), compared with values experimentally observed in Pb0-Si02 and Ca0-Si02 melts. Reprinted from Toop and Samis (1962b), with kind permission of ASM International, Materials Park, Ohio.
A function (such as energy) that is dependent only on the state of the system and not on the pathway as to how that state was reached. Examples of state functions include internal energy, enthalpy, entropy, Gibbs free... [Pg.647]

Here, JVi is equal to the change in Gibbs free energy (dG), which under the conditions of constant pressure is equal to the change in internal energy (dE) minus the product of the change in entropy and the Kelvin temperature as follows ... [Pg.291]


See other pages where Internal Gibbs free is mentioned: [Pg.347]    [Pg.393]    [Pg.418]    [Pg.835]    [Pg.447]    [Pg.50]    [Pg.1244]    [Pg.329]    [Pg.598]    [Pg.55]    [Pg.75]    [Pg.227]    [Pg.27]    [Pg.39]    [Pg.147]    [Pg.4]    [Pg.174]    [Pg.201]    [Pg.211]    [Pg.241]    [Pg.281]    [Pg.587]    [Pg.418]    [Pg.23]    [Pg.103]    [Pg.430]    [Pg.8]    [Pg.73]    [Pg.525]    [Pg.680]    [Pg.680]   
See also in sourсe #XX -- [ Pg.14 ]




SEARCH



Free Gibbs

© 2024 chempedia.info