Gibbs energy of vaporization

Tvap is the temperature at which the Gibbs energy of vaporization becomes zero. The value of A, difference between the A H values for the gas and liquid at Experimental values of... 

Since the system is closed, dtij = 0 and, therefore, dGj = 0 this requires the molar (or specific) Gibbs energy of the vapor to be identical with that of the liquid ... 

The vapor pressure of chlorine dioxide, Cl02, is 155 Torr at —22.75°C and 485 Torr at ().()0°C. Calculate (a) the standard enthalpy of vaporization (b) the standard entropy of vaporization (c) the standard Gibbs free energy of vaporization (d) the normal boiling point of C102. 

Molecular weight and Gibbs free energy of vaporization AGV (Burkhard et al. 1985a) ... 

Harris, K.R., Dunlop, P.J. (1970) Vapor pressures and excess Gibbs energies of mixtures of benzene with chlorobenzene, -hexane and -heptane at 25°C. J. Chem. Thermodyn. 2, 801-811. 

The mutual solubility of two liquids A and B depends, in general, on how much the molecules of each liquid tend to attract those of its own kind, relative to their tendency to attract those of the other. This tendency is measured by the excess Gibbs energy of mixing of the two liquids (see section 2.4), Am gL, which is related to the partial vapor pressures p/ and of the two liquids A and B in the mixture. If the composition of the system is given by and Wb moles of the respective components in a given phase, their mole fractions in this phase are... 

R.B. Cundall et al, "Vapor Pressure Measurements on Some Organic High Explosives , J-ChemSoc, Faraday Trans I, 74 (6), 1339—45 (1978) CA 89, 181933 (1978) [Equilibrium vap press were detd for various expls by the Knudson cell technique. The data for HMX follows the Clausius-Clapeyron eqtn. The values detd for the const A and B in the eqtn, log10p = A—(B/T), plus the std enthalpy, entropy and Gibbs energy of sublimation from the authors calcns are presented in Table 7 ... 

De Kruif, C.G., Van Generen, A.C.G., Bink, J.C.W.G., Oonk, H.A.J. (1981) Properties of mixed crystalline organic material prepared by zone levelling. II. Vapor pressures and excess Gibbs energies of (p-dichlorobenzene + />-dibromobenzene). J. Chem. Thermodynam. 13, 457 163. 

But the first two terms on the right are the Gibbs energies of pure liquid i pure vapor r at the pure-species equilibrium conditions T and Pf1 accor to Eq. (6.47), they are equal. The preceding equation therefore reduces to... 

Instrumental methods in chemistry make it possible to characterize any chemical compound by a very large number of different kind of measurements. Such data can be called observables. Examples are provided by Spectroscopy (absorbtions in IR, NMR, UV, ESCA. ..) chromatography (retentions in TLC, HPLC, GLC. ..) thermodynamics (heat capacity, standard Gibbs energy of formation, heat of vaporization. ..) physical propery measures (refractive index, boiling point, dielectric constant, dipole moment, solubility. ..) chemical properties (protolytic constants, ionzation potential, lipophilicity (log P)...) structural data (bond lengths, bond angles, van der Waals radii...) empirical structural parameters (Es, [Pg.34]

Figure 5.1 Gibbs energy of nucleation of water drops at different water vapor oversaturations of at 25°C. Curve 1 is plotted for oversaturation p/poo = 8.1 = 0.5...

The enthalpy of formation of YF3 was determined by Rudzitis, Feder, and Hubbard 164) using fluorine bomb calorimetry. NdCla was done by solution methods (179), and the enthalpies of formation of LaFs and PrFa were determined by Polyachenok 161) who employed an indirect equilibration technique. A recent torsion-effusion study of the vapor pressure of CeFs 115) yields second and third law values for the enthalpy of sublimation. The thermodynamics of the chlorination of rare earths with gaseous chlorine have also been investigated 144). Gibbs energies of formation were determined for CeClg by solid-state electromotive force techniques 41). 

DELGE = Standard Gibbs energy of formation of vapor at 298 K, kj/mol. 

Expressing the Gibbs energy of the liquid in terms of its vapor pressure and assuming that the vapor behaves ideally, i.e. G = + RT InP, for a case of a spherical surface... 

Acid-base properties of oxide surfaces are employed in many fields and their relationship with PZC has been often invoked. Adsorption and displacement of different organic molecules from gas phase was proposed as a tool to characterize acid-base properties of dry ZnO and MgO [341]. Hammet acidity functions were used as a measure of acid-base strength of oxides and some salts [342]. Acidity and basicity were determined by titration with 1-butylamine and trichloroacetic acid in benzene using indicators of different pAg. There is no simple correlation between these results and the PZC. Acid-base properties of surfaces have been derived from IR spectra of vapors of probe acids or bases, e.g. pyridine [343] adsorbed on these surfaces. The correlation between Gibbs energy of adsorption of organic solvents on oxides calculated from results obtained by means of inverse gas chromatography and the acceptor and donor ability of these solvents was too poor to use this method to characterize the donor-acceptor properties of the solids [344],... 

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