Nitrogen, thermodynamic data

Flame Temperature. The adiabatic flame temperature, or theoretical flame temperature, is the maximum temperature attained by the products when the reaction goes to completion and the heat fiberated during the reaction is used to raise the temperature of the products. Flame temperatures, as a function of the equivalence ratio, are usually calculated from thermodynamic data when a fuel is burned adiabaticaHy with air. To calculate the adiabatic flame temperature (AFT) without dissociation, for lean to stoichiometric mixtures, complete combustion is assumed. This implies that the products of combustion contain only carbon dioxide, water, nitrogen, oxygen, and sulfur dioxide. 

Studies on metal-pyrazole complexes in solution are few. The enthalpy and entropy of association of Co(II), Ni(II), Cu(II) and Zn(II) with pyrazole in aqueous solution have been determined by direct calorimetry (81MI40406). The nature of the nitrogen atom, pyridinic or pyrrolic, involved in the coordination with the metal cannot be determined from the available thermodynamic data. However, other experiments in solution (Section 4.04.1.3.3(i)) prove conclusively that only the N-2 atom has coordinating capabilities. 

Experimental thermodynamic data have been reported for dibenzo-l,4-thiazino[3,2-/ ][l,4]thiazine 166 <1997MI565> compared to the corresponding oxazinooxazine, replacement of oxygen by sulfur increases ring strain. Crystallographic data show that the nitrogen centres in 166 are /7-periplanar <1994JCM458>. 

From the thermodynamic data of Appendix C, show that the product of the reaction of ammonia gas with oxygen would be nitrogen, rather than nitric oxide, under standard conditions and in the absence of kinetic control by, for example, specific catalysis of NO formation by platinum. (Assume the other product to be water vapor.)... 

The theoretical yields of cyanogen obtained by the reaction of carbon and nitrogen can also be derived from thermodynamic data. At high temperatures cyanogen is partly dissociated into cyanogen radicals, and the following simultaneous equilibria must be considered ... 

Experimental thermodynamic data show that the N2 molecule is stable, is diamagnetic, and has a very high bond energy, 946 kj/mol. This is consistent with molecular orbital theory. Each nitrogen atom has seven electrons, so the diamagnetic N2 molecule has 14 electrons. 

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