A Simple Method To Calculate the Temperature Dependence of the Gibbs Energy and Chemical Equilibrium Constants

2014 ◽  
Vol 91 (3) ◽  
pp. 396-401 ◽  
Author(s):  
Francisco M. Vargas
Keyword(s):  
Gibbs Energy ◽  
Temperature Dependence ◽  
Chemical Equilibrium ◽  
Equilibrium Constants ◽  
Simple Method

On Temperature Dependence of Excess Gibbs Energy

1999 ◽  
Vol 64 (7) ◽  
pp. 1093-1099 ◽  
Author(s):  
Ivona Malijevská ◽  
Anatol Malijevský
Keyword(s):  
Heat Capacity ◽  
Gibbs Energy ◽  
Temperature Dependence ◽  
Excess Gibbs Energy ◽  
Excess Enthalpy ◽  
Excess Heat Capacity ◽  
Wilson Equation ◽  
Excess Heat ◽  
Energy Excess ◽  
Wilson And Nrtl Equations

Temperature dependence of GE is discussed for three widely used equations linear and nonlinear in parameters. It is shown that the Wilson equation predicts always positive excess heat capacity regardless of values of its parameters. Several temperature modifications of the Redlich-Kister, Wilson and NRTL equations are discussed with respect to the sign of the excess Gibbs energy, excess enthalpy and excess heat capacity.

scholarly journals Temperature dependence of the stacking-fault Gibbs energy for Al, Cu, and Ni

2018 ◽  
Vol 98 (22) ◽  
Author(s):  
Xi Zhang ◽  
Blazej Grabowski ◽  
Fritz Körmann ◽  
Andrei V. Ruban ◽  
Yilun Gong ◽  
...  
Keyword(s):  
Gibbs Energy ◽  
Temperature Dependence ◽  
Stacking Fault

scholarly journals Temperature dependence of the specific heat and thermodynamic functions AК1М2 alloy, doped strontium

2019 ◽  
Vol 21 (1) ◽  
pp. 35-42 ◽  
Author(s):  
I. N. Ganiev ◽  
S. E. Otajonov ◽  
N. F. Ibrohimov ◽  
M. Mahmudov
Keyword(s):  
Heat Capacity ◽  
Gibbs Energy ◽  
Specific Heat ◽  
Temperature Dependence ◽  
Specific Heat Capacity ◽  
Thermodynamic Functions ◽  
Inverse Relationship ◽  
Alloying Element ◽  
Enthalpy And Entropy ◽  
Increasing Temperature

In the heat «cooling» investigated the temperature dependence of the specific heat capacity and thermodynamic functions doped strontium alloy AK1М2 in the range 298,15—900 K. Mathematical models are obtained that describe the change in these properties of alloys in the temperature range 298.15—900 K, as well as on the concentration of the doping component. It was found that with increasing temperature, specific heat capacity, enthalpy and entropy alloys increase, and the concentration up to 0.5 wt.% of the alloying element decreases. Gibbs energy values have an inverse relationship, i.e., temperature — decreases the content of alloying component — is up to 0.5 wt.% growing.

Solubility of non-polar gases in cyclohexanone between 273.15 and 303.15 K at 101.32 kPa partial pressure of gas

1987 ◽  
Vol 65 (9) ◽  
pp. 2198-2202 ◽  
Author(s):  
María Asunción Gallardo ◽  
José María Melendo ◽  
José Santiago Urieta ◽  
Celso Gutierrez Losa
Keyword(s):  
Gibbs Energy ◽  
Partial Pressure ◽  
Temperature Dependence ◽  
Hard Sphere ◽  
Scaled Particle Theory ◽  
Sphere Diameter ◽  
Particle Theory ◽  
Enthalpy And Entropy

Solubility measurements of several non-polar gases (He, Ne, Ar, Kr, Xe, H2, D2, N2, O2, C2H4, C2H6, CF4, SF6, andCO2) in cyclohexanone at 273.15 to 303.15 K and a partial pressure of gas of 101.32 kPa, are reported. Gibbs energy, enthalpy, and entropy of solution at 298.15 K and 101.32 kPa partial pressure of gas were evaluated. Effective hard-sphere diameter temperature dependence has been studied and its effect on the calculated SPT (Scaled Particle Theory) solubilities, and enthalpies and entropies of solution was also examined.

scholarly journals A re-evaluation of the ClO/Cl<sub>2</sub>O<sub>2</sub> equilibrium constant based on stratospheric in-situ observations

2005 ◽  
Vol 5 (3) ◽  
pp. 693-702 ◽  
Author(s):  
M. von Hobe ◽  
J.-U. Grooß ◽  
R. Müller ◽  
S. Hrechanyy ◽  
U. Winkler ◽  
...  
Keyword(s):  
Temperature Dependence ◽  
Equilibrium Constant ◽  
Thermal Equilibrium ◽  
Loss Rate ◽  
Equilibrium Constants ◽  
The Arctic ◽  
Strong Temperature Dependence ◽  
Atmospheric Models ◽  
Ozone Loss

Abstract. In-situ measurements of ClO and its dimer carried out during the SOLVE II/VINTERSOL-EUPLEX and ENVISAT Validation campaigns in the Arctic winter 2003 suggest that the thermal equilibrium between the dimer formation and dissociation is shifted significantly towards the monomer compared to the current JPL 2002 recommendation. Detailed analysis of observations made in thermal equilibrium allowed to re-evaluate the magnitude and temperature dependence of the equilibrium constant. A fit of the JPL format for equilibrium constants yields KEQ=3.61x10-27exp(8167/T), but to reconcile the observations made at low temperatures with the existing laboratory studies at room temperature, a modified equation, KEQ=5.47x10-25(T/300)-2.29exp(6969/T), is required. This format can be rationalised by a strong temperature dependence of the reaction enthalpy possibly induced by Cl2O2 isomerism effects. At stratospheric temperatures, both equations are practically equivalent. Using the equilibrium constant reported here rather than the JPL 2002 recommendation in atmospheric models does not have a large impact on simulated ozone loss. Solely at large zenith angles after sunrise, a small decrease of the ozone loss rate due to the ClO dimer cycle and an increase due to the ClO-BrO cycle (attributed to the enhanced equilibrium ClO concentrations) is observed, the net effect being a slightly stronger ozone loss rate.

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