Lewisite chemical structures

Figure 7. Chemical structures of 2-chlorovinyldichloroarsine (lewisite LI), 2-chlorovinylarsonous acid (CVAA), British Anti-Lewisite (BAL) and the CVAA-BAL complex...

Figure 8. Chemical structures of 2-chlorovinyldichloroarsine (Lewisite LI), 2-chlorovinylarsonous acid (CVAA), British Anti-Lewisite (BAL) and the CVAA-BAL complex. (Reprinted from Toxicology and Applied Pharmacology, Vol. 184, D. Noort,H.P. BenschopandR.M. Black, Biomonitoring of Exposure to Chemical Warfare Agents A Review, pages 116-126 (2002), with permission from Elsevier Science.)...

Lewisite [dichloro(2-chlorovinyl)arsine] is an organic arsenical known for its vesicant properties (Rosenblatt et al., 1975). It has a molecular weight of 207.32, vapor pressure of 0.58 mm HG at 25°C, a liquid density of 1,89 g/cm at 25°C, freezing point of -18°C, boiling point of 190°C, and is negligibly soluble in water (DA, 1974). The chemical structure of lewisite is shown below. Lewisite may occur as a trans-isomer and as a cis-isomer. In aqueous solutions, the cis-isomer undergoes photoconversion to the trans-isomer (Clark, 1989). hi the presence of moisture, lewisite is rapidly converted to the more stable but highly toxic lewisite oxide (2-chlorovinylarsenous acid) (Cameron et al., 1946). 

TABLE 8.5. Nomenclature, chemical formulae, and chemical structure of lewisites... 

TABLE 8.5 Nomenclature, Chemical Formulae, and Chemical Structure of Lewisites... 

Fig. 4.3 Toxic and non-toxic the structural formulas of chemical weapon Lewisite, and non-toxic arsenobetaine (occurring in fish). (Authors own work)...

Figure 2.4 provides the structures and chemical names of selected blister agents and Table 2.4 lists the chemical and physical properties of blister agents. All blister agents are liquids at 20°C, with characteristic odors. The mustards are colorless to amber-colored, and lewisite ranges from a clear to brown liquid. HD, HN-3, and L are lower in VP than HN-1 and HN-2. The vapor density of each of the blister agents is heavier than air. 

After PINS confirmation, explosive shells are best detonated on-site as even unfused old ordnance can have hypersensitive crystals growing in the exudate that forms in the bottom of the shell as the explosives age. For single UXO on a range, the author believes in the as is where is philosophy for detonating explosive ordnance. Simply build a containment structure and sandbag it over the shell and detonate it where it is. However, chemical shells with Lewisite or other arsenicals will leave behind arsenic, which must be cleaned up after detonation. If not detonated where found for fear of touching off adjacent munitions, or because of the proximity of buildings or people, the UXO should be robotically moved as short a distance as possible for detonation. 

Besides Mustard and Lewisite, stockpiles of blister chemicals also include Mustard -Lewisite mixtures. Moreover, the stored Mustard -Lewisite mixtures have different structures for example, in one case it s a dual component Mustard -Lewisite system, while in another a mixture of Mustard -Lewisite in the solvent dichloroethane. 

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