Ammonia complicated

Whereas addition of hydrogen to feedwater helps solve the O2 or ECP problem, other complications develop. An increase in shutdown radiation levels and up to a fivefold increase in operating steam plant radiation levels result from the increased volatiUty of the short-Hved radioactive product nitrogen-16, N, (7.1 s half-life) formed from the coolant passing through the core. Without H2 addition, the in the fluid leaving the reactor core is in the form of nitric acid, HNO with H2 addition, the forms ammonia, NH, which is more volatile than HNO, and thus is carried over with the steam going to the turbine. 

The reaction of amines with alkyl halides was seen earlier (Section 22.7) as a complicating factor in the preparation of amines by alkylation of ammonia. 

Consider a more complicated example—the oxidation of ammonia, NHS ... 

Solution of alkali metals in liquid ammonia, containing the so-called solvating electrons, may be used as an alternative homogeneous system to initiate polymerization by an electron transfer process. This system suffers, however, from complications resulting from proton transfer from ammonia leading to the formation of NH2- ions, which in turn initiate further polymerization.4... 

In this example, only one of the reagents has a concentration that can vaiy, and each stoichiometric coefficient is one. What happens for a more complicated reaction Consider the synthesis of ammonia carried out in a pressurized reactor containing N2, H2, and NH3 at partial pressures different from 1 bar ... 

C14-0023. Atmospheric nitrogen can be transformed to ammonia by various bacteria that fix nitrogen. The overall process is complicated, but the net reaction can be written as... 

A. Preparation.—Halogen displacement reactions have been used to prepare a number of new aminofluorophosphines. Aminodifluorophos-phine (1) has been prepared for the first time, from either bromodifluoro-phosphine or chlorodifluorophosphine, and ammonia. Studies of its n.m.r. spectrum have been made (see Chapter 11). The related NN-difluoroaminodifluorophosphine (2) has been prepared, from difluoroiodo-phosphine, and found to be explosive. Two syntheses of A-alkyl-amino-difluorophosphines have been reported, one of which was complicated by the subsequent formation of the phosphorane (3) and the bis-(A-alkylamino)fluorophosphine (4). 

Carothers claimed that he kept going only because he finally received one of Illinois few scholarships, 750 embellished with esteem. But he must also have persevered because he loved chemistry. As he admitted, even the smell of his laboratory coat, saturated with the inexpressibly pungent and complicated odors of lab no. 219 [filled him] with a nostalgia to return to the atmosphere of sweetly blended sulfur dioxide, bromine, chlorine, ammonia, hydrogen chloride, phosgene, chloroacetone, etc., etc., etc. ... 

For reasons of safety and toxicity, urea is the preferred selective reducing agent for mobile SCR applications. Under the hydrothermal conditions in the exhaust system, urea decomposes to ammonia which reduces the nitrogen oxides on the surface of the SCR catalyst [18,19], If urea is used instead of ammonia, the DeNO chemistry involves isocyanic acid as an important intermediate which will lead to a complication of the SCR chemistry [20],... 

In the example given in the text above, with 4 mol of nitrogen, it was not necessary to use the factor-label method the numbers were easy enough to work with. However, when the numbers get even slightly complicated, it is useful to use the factor-label method. Note that any of the following factors could be used for this equation, but we used the one above because it is the one that changes moles of hydrogen to moles of ammonia. 

MePO2- or PME2- (Table XIX), but the open closed equilibrium lies very much on the side of the chelated form of the complex (87% for the Ca2+ complex - compare 15% for [Ca(atp)]2 and just 7% for [Ca(amp)] (695)). The availability of stability constants both for methylphosphonate and for benzimidazole (a purine model) complexes means that the chelate effect for complexes of (1H-benzimidazol-2-yl-methyl)phosphonate can be discussed without the usual complications, such as the differences between ethane-1,2-diamine and two ammonia or two methylamine ligands and disparities between units (704). 

Reductions of alkyllead halides with LiAlFLt are among the most successful ones and are, despite complications in some cases241, easy to perform. R3PbCl can easily be reduced in liquid ammonia by KBH4239 241 through an R3PbBH4 intermediate that is converted into the trialkyllead hydride by NH3 ... 

Widespread medicinal use of colloidal bismuth subcitrate (CBS) has prompted extensive studies of bismuth compounds involving the citrate anion. Bismuth citrate is essentially insoluble in water, but a dramatic increase in solubility with increasing pH has been exploited as a bio-ready source of soluble bismuth, a material referred to as CBS. Formulation of these solutions is complicated by the variability of the bismuth anion stoichiometry, the presence of potassium and/ or ammonium cations, the susceptibility of bismuth to oxygenation to Bi=0, and the incorporation of water in isolated solids. Consequently, a variety of formulas are classified in the literature as CBS. Solids isolated from various, often ill-defined combinations of bismuth citrate, citric acid, potassium hydroxide, or ammonium hydroxide have been assigned formulas on the basis of elemental analysis data or by determination of water and ammonia content, but are of low significance in the absence of complementary data other than thermal analysis (163), infrared spectroscopy (163), or NMR spectroscopy (164). In this context, the Merck index lists the chemical formula of CBS as KgfNHJaBieOafOHMCeHsCbh in the 11th edition (165), but in the most recent edition provides a less precise name, tripotassium dicitrato bismuthate (166). 

HE is a common complication of cirrhosis and requires clinical vigilance and treatment with dietary restriction, elimination of CNS depressants, and therapy to lower ammonia levels. 

Burkheiser Also known as the sulfite-bisulfite process. A complicated process for removing hydrogen sulfide and ammonia from coal gas by absorption in an aqueous solution containing ammonia, iron oxide, and elemental sulfur. The end products are sulfur and ammonia. Invented by K. Burkheiser in 1907 and developed in Germany in the early 1900s. 

The enthalpy of solution of the ammoniate LaI3-6NH3 in liquid ammonia at 25°C is -178.5 kJ mol-1. This value is close to that at infinite dilution, for it was determined at a concentration of Lal3 in the product solution of only 1 in 18,500 (224). Comparisons of this value with those for other iodides, or for aqueous media, are complicated by the fact that the ammoniate rather than anhydrous Lal3 was used for this calori-... 

The vivid interest in hydrazine as a powerful propellant has stimulated many investigations both of its thermal decomposition and of its oxidation. Although hydrazine decomposes much more readily than ammonia, the study of its homogeneous decomposition by classical means using a static system is complicated considerably by wall catalysis. Thus, other experimental techniques have had to be applied, e.g. decomposition flames, flash photolysis, studies of explosion characteristics and the shock-tube technique. 

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