Soman physical properties

Physical Properties. Pure soman is a colorless liquid with a somewhat fruity odor. It has density 1.01 g/mL (20°C), vapor pressure of 0.27 mm/Hg (20°C), mp of —80°C, and bp of 190°C (85°C at 15 mm/Hg). Distillation is accompanied by decomposition that begins near 130°C. Soman s solubility in water is about 20% at 25°C. It is only about 20% as soluble in water as is tabun. With two different chiral centers, it exists as four stereoisomers (Benschop et al., 1985), each with a different toxicity. The lethal concentration (inhalation) in humans is estimated at approximately 25-50 mg min/m (Somani et al., 1992). 

Molecular models of the nerve agents tabun, sarin, soman, and VX are shown in Figure 5-3. Table 5-3 summarizes the chemical, physical, environmental and biological properties of these compounds. 

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