Search Results
equation Excess thermodynamic functions The deviation from the ideal behavior can best be expressed in terms of excess thermodynamic functions, namely, excess free energy ( g E ), excess enthalpy ( h E ), and excess
Thermal and physico-chemical studies on binary organic eutectic systems
4-Aminoacetophenone with benzoin and 4-nitrophenol
.27 The deviation from the ideal behavior can best be expressed in terms of excess thermodynamic functions, namely, excess free energy ( g E ), excess enthalpy ( h E ), and excess entropy ( s E ) which give more quantitative idea about the nature of
thermodynamic characteristics and interpret them in terms of physical chemistry, to calculate the standard thermodynamic functions C p 0 (T), H °( T ) − H °(0), S °( T ) − S °(0) and G °( T ) − H °(0) over the temperature range from T → 0 to (550–580) K
Abstract
The heat capacity of solid NdBr3 was measured by Differential Scanning Calorimetry in the temperature range from 300 K up to the melting temperature. The heat capacity of liquid NdBr3 was also determined. These results were least-squares fitted to a temperature polynome. The melting enthalpy of NdBr3 was measured separately. DSC was used also to study phase equilibrium in the NdBr3-LiBr system. The results obtained provided a basis for constructing the phase diagram of the system under investigation. It represents a typical example of simple eutectic system. The eutectic composition, x(NdBr3)=0.278, was obtained from the Tamman construction. This eutectic mixture melts at 678 K. The electrical conductivity of NdBr3-LiBr liquid mixtures and of pure components was measured down to temperatures below solidification. Reflectance spectra of the pure components and their solid mixtures (after homogenisation in the liquid state) with different composition were recorded in order to confirm the reliability of the constructed phase diagram.
Summary As part of a larger study of the physical properties of potential ceramic hosts for nuclear wastes, we report the molar heat capacity of brannerite (UTi2O6) and its cerium analog (CeTi2O6) from 10 to 400 K using an adiabatic calorimeter. At 298.15 K the standard molar heat capacities are (179.46±0.18) J K-1 mol-1 for UTi2O6 and (172.78±0.17) J K-1 mol-1 for CeTi2O6. Entropies were calculated from smooth fits of the experimental data and were found to be (175.56±0.35) J K-1 mol-1 and (171.63±0.34) J K-1 mol-1 for UTi2O6 and CeTi2O6, respectively. Using these entropies and enthalpy of formation data reported in the literature, Gibb’s free energies of formation from the elements and constituent oxides were calculated. Standard free energies of formation from the elements are (-2814.7±5.6) kJ mol-1 for UTi2O6 and (-2786.3±5.6) kJ mol-1 for CeTi2O6. The free energy of formation from the oxides at T=298.15 K are (-5.31±0.01) kJ mol-1 and (15.88±0.03) kJ mol-1 for UTi2O6 and CeTi2O6, respectively.
functions, g ( α ). The activation energy, E , and pre-exponential factor, A , were estimated. The transition state thermodynamic functions, Δ H *, Δ G * and Δ S *, were calculated via the activated complex theory. Experimental
) and thermodynamic functions (Δ H ∗, Δ G ∗, and Δ S ∗) via the Kissinger method is reported on the basis of thermal analysis techniques. To the best of our knowledge, such a facile and acetone-mediated synthesis route, kinetic and thermodynamic studies
by the AC and DSC techniques. Two special thermal phenomena were discovered and the mechanism was deduced. The temperature, T trs , molar enthalpies, Δ trs H m , molar entropies, Δ trs S m , of the phase transitions and thermodynamic functions, [ H T
Introduction Studies involving the determination of thermodynamic functions as a function temperature have gained importance in view of the insight they provide about systems behavior at micro level at the temperature studied
Thermodynamics of the coordination compound Zn(Met)(NO3)2·1/2H2O(s) (Met = l-α-methionine)
Low temperature heat capacities and the standard molar enthalpy of formation
polynomial equation of heat capacities ( C p,m ) as a function of reduced temperature ( X ), [ X = f ( T )], by a least squares method so as to calculate smoothed heat capacities and various thermodynamic functions of the coordination compound
