Nitrogen family properties

Bismuth, Bi, the 83rd element of the periodic table is the most metallic and the least abundant of the elements in the nitrogen family (group 15). It has an atomic mass of 208.980 and a ground state electronic configuration of [Xe] 4f 5d %s 6p. The bismuth atom usually utilizes the three 6p electrons in bond formation and retains the two 6s electrons as an inert pair, hence the oxidation state -1-3 exhibited by bismuth in the vast majority of its compounds. However, a variety of organobismuth compounds can contain the element in the -1-5 oxidation state. Coordination numbers are 2, 3,4, 5 and 6. Bismuth not only has metallic characteristics but also exhibits many properties similar to those of semiconductors and insulators. Consequently, it is often classified as a semi-metal or metalloid. Bismuth compounds are usually colorless unless the metal is bound to a chromophore. 

Chemical composition does not generally come into play, except for the case where it is necessary to establish maximum specifications for undesirable compounds such as sulfur, nitrogen, and metals, or even more unusually, certain compounds or families of compounds such as benzene in premium gasolines. By tradition, the refiner supposedly possesses numerous degrees of freedom to generate products for which the properties but not the composition are specified. 

The substitution of oxygen by nitrogen in PO4 tetrahedron has allowed the synthesis of a new family of solids with original properties the nitrided phosphates. These systems (e.g., AlPON, AlGaPON) with tunable acid-base properties are used in a growing number of intermediate and fine chemistry production processes [204] as well as supports in heterogeneous catalysis (e.g., dehydrogenation reactions) [205]. 

Among the heterocyclics there is one group which will be thoroughly examined the pyrazines. The compounds belonging to this family play a very important role as contributors of desirable food flavor properties. Structurally, pyrazines are heterocyclic nitrogen compounds and their formation is a quite complicated process. Maga and Sizer (4) present a summary of these formation pathways. 

The beanlike seeds of the trees and shrubs of the genus Erythrina, a member of the legume family, contain substances that possess curare-like activity. The plants are widely distributed in the tropical and subtropical areas of the American continent, Asia, Africa, and Australia, but apparently they are not used by the natives in the preparation of arrow poisons. Of 105 known species, the seeds from more than 50 have been tested, and all were found to contain alkaloids with curariform properties. Erythroidine, from E. americana, was the first crystalline alkaloid of the group to be isolated. It consists of at least two isomeric alkaloids, a and P-erythroidine both are dextrorotatory. Most experimental and clinical study has centered on the b form because it is more readily obtainable in pure state. P-Erythroidine is a tertiary nitrogenous base. Several hydrogenated derivatives of p-erythroidine have been prepared of these, dihydro-P-erythroidine has been studied most carefully and subjected to clinical trial. Conversion of P-erythroidine into the quaternary metho salt (p-erythroidine methiodide) does not enhance, but rather almost entirely, abolishes its curariform activity this constitutes a notable exception to the rule that conversion of many alkaloids into quaternary metho salts results in the appearance of curare-like action. 

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