Chemical agents physical properties

Ghromium(III) Compounds. Chromium (ITT) is the most stable and most important oxidation state of the element. The E° values (Table 2) show that both the oxidation of Cr(II) to Cr(III) and the reduction of Cr(VI) to Cr(III) are favored in acidic aqueous solutions. The preparation of trivalent chromium compounds from either state presents few difficulties and does not require special conditions. In basic solutions, the oxidation of Cr(II) to Cr(III) is still favored. However, the oxidation of Cr(III) to Cr(VI) by oxidants such as peroxides and hypohaUtes occurs with ease. The preparation of Cr(III) from Cr(VI) ia basic solutions requires the use of powerful reducing agents such as hydra2ine, hydrosulfite, and borohydrides, but Fe(II), thiosulfate, and sugars can be employed in acid solution. Cr(III) compounds having identical counterions but very different chemical and physical properties can be produced by controlling the conditions of synthesis. 

The number and the type of amino acids and their sequence determine the surface charge of the protein, its molecular configuration and its unique chemical and physical properties. The function of a protein is dependent on its three-dimensional structure. A number of agents can dismpt this structure thus denaturing it, for example changes in pH, temperature, salt concentration, and the presence of reducing substances. 

Unless otherwise indicated, chemical and physical properties are for the pure or production quality material. Properties of mixed, binary, thickened, or dusty agents, even those in solutions, will have physical and chemical properties that vary from the listed values. These variations will depend on the proportion of agent to other materials (e.g., solvents, thickener, etc.) and the properties of these other materials. If available, data on mixtures or modified agents (e.g., salts) are included. For any given parameters, a dash (i.e., —) means that the value is unavailable because it has not been determined or has not been published. 

In water solution astatine resembles iodine in some of its chemical and physical properties. Both are powerful oxidizing agents. 

Exposure data and other information on an agent under consideration are also reviewed. In the sections on chemical and physical properties, on analysis, on production and use and on occurrence, published and unpublished sources of information may be considered. 

The diffusion of a xenobiotic agent depends both on its chemical and physical properties ... 

Depending on the amount of amine used and on the milling time, the reaction mass either had a pastelike consistency or that of a fluid dispersion. The experiments were intended to establish some parameters (duration of mechanical processing, amount of diamine and complexing agent, etc.) and correlate them to characterize the polymers obtained, and to determine certain chemical and physical properties of the polymer. In all cases, the samples were purified by extraction in a Soxhlet apparatus with water or alcohol to remove unreacted ethylenediamine and metallic salts. The extractions were carried out until constant weight was obtained. Total removal of chloride was determined by silver nitrate. Purified samples were then washed with methanol, dried, and analyzed. 

For the purpose of implementing the CWC, toxic chemicals and precursors, which have been identified for the application of verification measures, are listed in Schedules contained in the Annex on Chemicals (for the Schedules, see Chapter 2). Schedule 1 includes chemicals developed, produced, stockpiled, or used as a chemical weapon as defined above, and chemicals structurally close to them. Schedule 2 lists three toxic chemicals not included in Schedule 1 and the degradation products and precursors of these toxic chemicals as well as of those of Schedule 1. Schedule 3 lists four toxic chemicals and precursors not listed in the other Schedules. The Schedules contain mainly organic chemicals with different chemical and physical properties, being neutral chemicals, acids, bases, volatiles, and nonvolatiles, where phosphorus, fluorine, sulfur, chlorine, nitrogen, and oxygen occur frequently. Riot control agents are not included in the Schedules. 

The free acid and its salts are transformed into bis(5-thiatriazolyl) disulfide (69) by various oxidizing agents. Chemical and physical properties of this highly explosive solid have been reviewed elsewhere (64AHC(3)263>. 

---