Calorimetric data, tables experiment

The energy equivalent of the calorimeter, e, and the enthalpy of the isothermal calorimetric process, A//icp, were derived from equations 8.2 and 8.4, respectively. The standard enthalpy of reaction 8.5 was computed as Ar//°(8.5) = AZ/icp/n, where n is the amount of substance of Mo(ri5-C5H5)2(C2H4) used in the experiment. The data in table 8.1 lead to a mean value Ar//°(8.5) = — 186.0 2.1 kJ mol-1, where the uncertainty is twice the standard deviation of the mean (section 2.6). This value was used to calculate the enthalpy of reaction (8.6), where all reactants and products are in their standard reference states, at 298.15 K, from... 

Using the combined protocol, the calorimetric as well as the infrared data of all six experiments were successfully modelled by Equation 8.25 (A q = 58 W2, A A = 0.284) and the associated reaction model parameters. The kinetic parameters determined (k[, k2, ordpB, ordppp) as well as the reaction enthalpies (ArHi and ArH2) are listed in Table 8.3. The qualities of the fits to the model for the separate calorimetric (A q = 45 W2, A A = 0.326) and infrared (A q = 104 W2, A A = 0.282) protocols were similar to that for the combined protocol. 

The thermal data of the reaction are summarized in Table 5.4. It should be noted that these criteria do not use any explicit kinetic data, but only the results of calorimetric experiments. For the decomposition reaction, by taking the activation energy into account, the safety limits of TD24 = 113 °C and Tm = 122 °C may be established, according to the assessment criteria presented in Section 3.3.3. The activation energy may be determined, for example, from DSC experiments, as described in Chapter 11. Without knowledge of the process conditions of temperature and feed rates, the assessment remains global, as shown in Table 5.4. More detailed assessment will be provided in the next chapters for different reactor types and process conditions. 

Maier, Suponitskii, and Karapet yants prepared anhydrous crystalline lanthanum, praseodymium, and neodymium selenite by keeping the amorphous salts at an elevated temperature in a sealed tube. The salts are denoted by M2(Se03)3. The standard enthalpies of formation of the compounds have been calculated from the experimental results and auxiliary data in Table A-87. The solvent (sin) employed in the calorimetric dissolution experiments was HCI(aq, 1 18.5). Dissolution was made to the appropriate concentrations and the composition of the solutions will be denoted simply as dilute (dil). 

The hydrolysis of Af was not considered in the evaluation of the result in [73SEL/ZAL]. The equilibrium constants in [76BAE/MES] were used to estimate the concentrations of the hydroxo complexes formed under the conditions of the calorimetric experiment. Thus only formation of AlOH AljCOH), and Al3(OH)f was considered. Of the total Al(lll), AP comprised 98.4%. The enthalpy change per mole of OH bound is about (40.0 + 5.0) kJ according to the same Reference. The evaluation of the experimental data by the review is shown in Table A-94. 

The enthalpies and entropies of formation of intermetallic compounds between transition metals and rare earth or actinide elements are reported in tables 5-15. As can be seen, data are available for late transition metals. For early transition metals some data concerning the U-Zr, U-Nb, U-Mo solid solutions have been found and are reported in table 16. When calorimetric experiments have been performed in the liquid state, the values of the partial or integral enthalpies of mixing are reported in tables 17-20. These data concern only rare-earth-based alloys with Ni, Co, Fe and Mn. 

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