Thermodynamic data tables

Lattice constants for Pd-Rh alloys quenched from 1300°C vary smoothly with composition, showing only a small positive deviation from Vegard s law, but prolonged vacuum annealing below 850°C revealed the existence of a wide miscibility gap 151). Figure 25 shows the limits of the miscibility gap calculated from the lattice constants of the two-phase system between 825° and 600°C. Recent thermodynamic data (Table I) confirm the tendency to phase separation. The enthalpies of formation are endothermic... 

Thermodynamic data tables, choosing reference states for, 24 644 Thermodynamic efficiency batteries, 3 414... 

Since this is independent of pH, it is simply a horizontal line at the lower left of Fig. 15.3. The value of E° used in Eq. 15.52 is somewhat more negative than the widely cited —0.409 V derived from the U.S. National Bureau of Standards (now the National Institute of Standards and Technology) thermodynamic data tables (cf. Appendix C). In fact, since various values between —0.409 and —0.475 V have been reported by experienced experimentalists using several different methods, the value selected here is intended to be a conservative compromise.8 The moral is that one should not place blind faith in tabulated data, even from the most authoritative sources. 

Thermodynamic data (Tables 2.12 to 2.14) indicate that the salt is unstable above 500 K. 

The melting point of Cs2C03 is 1065 K.23 Transitions are listed in Table 2.21. Very little is known of its decomposition, but the thermodynamic data (Tables 2.22 to 2.24) indicate considerable thermal stability. 

Thermodynamic data (Tables 2.26 to 2.28) indicate that CoC03 is unstable toward decomposition above 400 K. 

There are some discordant experimental decomposition studies [87], but the thermodynamic data (Tables 4.127 to 4.129) indicate stability to near 1500 K. Data for SrO are in Table 2.79. 

During the past few years, a large number of crystal and NMR structures (Table I), structure-based mutations (Table II) and thermodynamic data (Table III) have become available. These studies have led to a much more advanced understanding towards the molecular basis of signaling transduction of the TNFR superfamily. 

The next step is to inspect the thermodynamic data (Table A.5) for the overall reaction and this is done at three temperatures, 298.15 K, 900 K and 1300 K, representing SPFC, MCFC and SOFC, respectively. Only at PqTq does the thermodynamic data favour the electrically driven reformer. Figure A.4 is for the major calculation route at PqTo. The production of hydrogen at both reformer electrodes in the figure is unusual, if the mind has been concentrating on fuel cells. Moreover, v=l. 

Also, relevant thermodynamic data (Table 4.2) indicate that the rise of the methane pressure during standard aromatization of C2 C4 alkanes must result in the direct insertion of methane into aromatic hydrocarbons at 720 770 K (450 500°C) that is, by reaction 2C3H8 -F CFI4 CgFIsCFIs + 6FI2 (see Table 4.2). 

In this system also the 2 1 complex with as-2-butene is significantly more stable than that of trcms-2-hnteine. The thermodynamic data (Table III) show that the stability difference is almost completely due to differences in the entropy change contrary to that observed with alkenyl... 

Thermodynamics of partial reactions. On the basis of thermodynamic data (Table 2) the energetics of the reduction of CO2 to CH4 can be divided into three parts, the energy coupling of which can be tested experimentally with cell suspensions the reduction of CO2 to methylene-H4MPT (CH2=H4MPT, formaldehyde level), the conversion of methylene-H4MPT to methyl-coenzyme M (CH3-S-C0M, methanol level), and the reduction of CH3-S-C0M to CH4 (Fig. 4). 

CaCOsCcalcite) + COjCg) + HjO = Ca + 2HCOj and the thermodynamic data table ... 

Figure VIII-2 Observed [1981SMI/MES] and calculated solubility of ThF4(cr, hyd) at 25°C (a) and 50°C (b) in 4.6 m HNO3 as a function of the free fluoride ion concentration. The soUd line depiets predieted total thorium eoneentration and the other lines depict predicted eoncentrations of different thorium speeies as marked, based on NONLtNT-SlT ealcnlations with the ion interaetion parameters (Table Vm-8) and thermodynamic data (Table VIII-9) selected in this review. ...

Figure IX-2 Observed and predicted aqueous concentrations at 25°C for solvent extraction studies in Na2S04 solutions [1963ALL/MCD], The solid line depicts the predicted total aqueous thorium concentration and the other lines depict the predicted concentrations of the individual thorium species in the aqueous phase as indicated, based on thermodynamic data (Table IX-5) and ion interaction parameters (Table IX-2) selected in this review.

Figure IX-7 Observed and predicted concentrations at 16°C in eqnilibrium with Th(S04)2 9H20(cr) and Th(S04)2-Na2S04-6H20(cr) in the presence of Na2S04 ([1910BAR], [191IBAR]). The solid lines depict predicted total thorinm concentrations in equilibrium with different solid phases and the other hnes depict predicted concentrations of different thorinm species as marked, based on thermodynamic data (Table lX-5) and ion interaction parameters (Table lX-2) selected in this review.

The thermochemical cycle in Scheme 6 has been used to estimate the effect of a one-electron oxidation on the thermodynamic acidities of metal hydrides. The method has been similarly used on organic systems. Measurement of the oxidation potentials for the metal hydride and its conjugate base gives access to relative values for the metal hydride and its one-electron oxidized counterpart through Equation (14), Scheme 6. In many reported cases, one (or even both) electrode potentials are obtained from chemically irreversible voltammograms, with consequential uncertainties in the derived thermodynamic data. Table 7 gives a comprehensive list of M-H data comparing MH and MH species as determined with this thermochemical cycle. 

In thermodynamic data tables (standard enthalpies or Gibbs energies of formation and standard molar entropies) which relate to compounds other than ions in a solution, the common convention that is applied involves setting the values of standard enthalpy and standard Gibbs energy of formation (or chemical potential) equal to OJmor for all simple pure elements in their stable physical state at the temperature in question. The data therefore refer to the formation of substances from simple elements. 

Table 3.1 shows an extract from a thermodynamic data table at 25 °C. Table 3.1 - Thermodynamic data ...

Remember that in thermodynamic data tables (standard Gibbs energies and enthalpies of formation) the following conventions are used ... 

An examination of the thermodynamic data tables of the National Bureau of Standards (1) and Russian Academy of Science (2) present different pictures of the solution composition. The NBS table does not point to any ion pairing while the Russian table indicates the existence of the CoCl" complex. The free energy values and resulting formation constant for 25° C from the Russian table are ... 

A uniform view of complexes in a cupric chloride solution is found in the NBS (1) and Russian (2) thermodynamic data tables. Both present data for not only the CuCl complex, but also the aqueous molecule CuClj ... 

Flashing. The flash from a superheated liquid released to atmospheric pressure can be estimated in a number of ways. If the initial and final state of the release is quiescent, then the initial and final enthalpies are the same (this does not imply a constant enthalpy process). For pure materials, such as steam, a Mollier entropy-enthalpy diagram or a thermodynamic data table can be used. 

Simple electrostatic arguments suggest that the free energy of ionized species is inversely proportional to the dielectric constant of the medium in which the ions reside. This should be so because ions interact more strongly with the molecules of polar solvents than with those of nonpolar solvents. This trend is indeed observed in thermodynamic data. Table 2 contains a compilation of the solubilities of a... 

Out of the above discussions, two points appear worthy of note. First, the extracted thermodynamic data (Table 2) for muscovite are comparable to those obtained by calorimetric methods. 

If the hydrogen were stored in a liquid form, the tank volume could be decreased, but insulation would be needed to prevent excessive boil-off. The ideal gas law would definitely not be appropriate for liquid H2 storage, and direct saturated and liquid thermodynamic data tables for hydrogen would be appropriate. 

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