Thermodynamic properties of (n-alkoxyethanols + organic solvents). XII. Total vapour pressure measurements for (n-hexane,n-heptane or cyclohexane + 2-methoxyethanol) at different temperatures

2001 ◽  
Vol 33 (1) ◽  
pp. 47-59 ◽  
Author(s):  
F.Javier Carmona ◽  
Venkat R. Bhethanabotla ◽  
Scott W. Campbell ◽  
J. Antonio González, ◽  
Isaías García de la Fuente ◽  
...  
Keyword(s):  
Thermodynamic Properties ◽  
Organic Solvents ◽  
Vapour Pressure ◽  
Pressure Measurements ◽  
Different Temperatures

scholarly journals Thermodynamic properties of the liquid Hg-Tl alloys determined from vapour pressure measurements

2002 ◽  
Vol 38 (3-4) ◽  
pp. 237-247 ◽  
Author(s):  
W. Gierlotka ◽  
K. Fitzner ◽  
M. Sukiennik
Keyword(s):  
Thermodynamic Properties ◽  
Activity Coefficients ◽  
Thermodynamic Functions ◽  
Vapour Pressure ◽  
Pressure Measurements ◽  
Temperature Range ◽  
Liquid Solutions ◽  
Partial Vapour Pressure

The partial vapour pressure of mercury over liquid Hg-Tl liquid solutions were determined in the temperature range from 450 to 700 K by direct vapour pressure measurements carried out with the quartz gauge. From the measured ln pHg vs. T relationships activities of mercury were determined. Using Redlich-Kister formulas logarithms of the activity coefficients were described with the following equations: From which all thermodynamic functions in the solutions can be derived.

Thermodynamic properties of the alkali metal hexachloroniobate and hexachlorotantalate compounds by vapour pressure measurements

1978 ◽  
Vol 56 (19) ◽  
pp. 2538-2545 ◽  
Author(s):  
Donald R. Sadoway ◽  
S. N. Flengas
Keyword(s):  
Thermodynamic Properties ◽  
Alkali Metal ◽  
Metal Cation ◽  
Vapour Pressure ◽  
Binary Systems ◽  
Alkali Metal Cation ◽  
Pressure Gauge ◽  
Pressure Measurements ◽  
Partial Pressures ◽  
Fused Quartz

The vapour pressures for the decomposition of the solid and liquid compounds AMCl6 where A = Na, K, Rb, or Cs, and M = Nb or Ta, were measured by a fused quartz Bourdon spiral pressure gauge. The hexachlorotantalates were found to be more stable thermally than the hexachloroniobates. Enthalpies of decomposition were calculated. The dissociation temperatures of each sequence of compounds increase with increasing size of the radius of the alkali-metal cation. Partial pressures of NbCl5 or TaCl5 vapour in equilibrium with solutions representing the binary Systems KCl–KNbCl6 and KCl–KTaCl6, respectively, are also reported.

A vapour-pressure study of mixtures of bromine and chlorine

1968 ◽  
Vol 21 (2) ◽  
pp. 287 ◽  
Author(s):  
GH Chessman ◽  
DL Scott
Keyword(s):  
Binary System ◽  
Thermodynamic Properties ◽  
Phase Equilibria ◽  
Phase Diagrams ◽  
Vapour Pressure ◽  
Pressure Measurements ◽  
Compound Formation

Phase equilibria in the system bromine-chlorine have been examined by vapour-pressure measurements, with a primary view to obtaining information on the nature of the solid mixtures. The work has led to some modification of the earlier phase diagrams and to a general discussion on the thermodynamic properties of this binary system in which compound formation is known to occur.

Vapour-pressure measurements and thermodynamic properties; 1,3,5-tribromobenzene

2010 ◽  
Vol 107 (3) ◽  
pp. 273-277 ◽  
Author(s):  
J. Huinink ◽  
J. C. van Miltenburg ◽  
H. A. J. Oonk ◽  
A. Schuijff
Keyword(s):  
Thermodynamic Properties ◽  
Vapour Pressure ◽  
Pressure Measurements

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

2016 ◽  
Vol 20 (2) ◽  
pp. 174-180 ◽  
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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