ABSTRACT
H3C NO2 Note: Impurities in commercially available nitromethane identified by GLC include 1-nitropropane, 2-nitropropane, acetaldehyde, acetonitrile, methanol, ethanol. In addition, formaldehyde, ethyl acetate, and acetone may be present (Jarosiewicz and Szychlinski, 1980) CASRN: 75-52-5; DOT: 1261; DOT label: Combustible liquid; molecular formula: CH3NO2; FW: 61.04; RTECS: PA9800000; Merck Index: 12, 6708 Physical state, color, and odor: Colorless liquid with a strong, disagreeable odor. Odor threshold concentration is 3.5 ppm (quoted, Amoore and Hautala, 1983). Melting point (°C): -29 (Windholz et al., 1983) Boiling point (°C): 99.98 (Dreisbach and Shrader, 1949) Density (g/cm3): 1.13754 at 20.00 °C, 1.12394 at 30.00 °C, 1.11029 at 40.00 °C (Lee and Tu, 1999) 1.1322 at 25 °C (Windholz et al., 1983) Diffusivity in water (x 10-5 cm2/sec): 1.27 at 20 °C using method of Hayduk and Laudie (1974) Dissociation constant, pKa: 10.21 at 25 °C (Dean, 1973) Flash point (°C): 35 (NIOSH, 1997) Lower explosive limit (%): 7.3 (NIOSH, 1997) Entropy of fusion (cal/mol⋅K): 9.474 (Jones and Giauque, 1947) Heat of fusion (kcal/mol): 2.319 (Jones and Giauque, 1947) Henry’s law constant (x 10-5 atm⋅m3/mol): 2.22 at 25 °C (Rohrschneider, 1973) 2.24 at 20.00 °C, 3.61 at 30.00 °C, 5.40 at 40.00 °C, 7.97 at 50.00 °C (inert gas stripping, Beneš
and Dohnal, 1999) Interfacial tension with water (dyn/cm): 5.7 at 25 °C (Murphy et al., 1957)
9.66 at 20 °C (Harkins et al., 1920) Ionization potential (eV): 11.08 (Lias, 1998) Soil organic carbon/water partition coefficient, log Koc: Unavailable because experimental methods for estimation of this parameter for nitroaliphatics are lacking in the documented literature. However, its high solubility in water and low Kow suggest its adsorption to soil will be low (Lyman et al., 1982). Octanol/water partition coefficient, log Kow: -0.33 (shake flask-GLC, Hansch and Anderson, 1967) -0.35 (Hansch and Leo, 1979) Solubility in organics: Soluble in acetone, alcohol, ether (Weast, 1986), and N,N-dimethylformamide (Windholz et al., 1983). Solubility in water (wt %): 9.0 at 0 °C, 9.7 at 9.5 °C, 10.4 at 19.7 °C, 11.7 at 31.0 °C, 12.8 at 40.4 °C, 14.8 at 50.0 °C, 15.1 at 60.5 °C, 17.1 at 70.5 °C, 19.6 at 80.2 °C, 20.8 at 89.8 °C (shake flask-GC, Stephenson, 1992) Vapor density: 2.49 g/L at 25 °C, 2.11 (air = 1) Vapor pressure (mmHg): 33.56 at 23.353 °C, 36.44 at 24.807 °C, 38.22 at 25.758 °C (Jones and Giauque, 1947) 27.8 at 20 °C, 46 at 30 °C (quoted, Verschueren, 1983) 35.26 at 25.00 °C (GC, Hussam and Carr, 1985) Environmental fate: Chemical/Physical. Nitromethane will not hydrolyze because it does not contain a hydrolyzable functional group. Exposure limits: NIOSH REL: IDLH 750 ppm; OSHA PEL: TWA 100 ppm (250 mg/m3); ACGIH TLV: TWA 20 ppm (adopted). Symptoms of exposure: An irritation concentration of 500.00 mg/m3 in air was reported by Ruth (1986). Toxicity: LC50 (96-h) for fathead minnows >650 mg/L (Spehar et al., 1982). Acute oral LD50 for mice 950 mg/kg, rats 940 mg/kg (quoted, RTECS, 1985). LD50 (intraperitoneal) for mice 110 mg/kg (quoted, RTECS, 1985). Uses: Rocket fuel; coatings industry; solvent for cellulosic compounds, polymers, waxes, fats; gasoline additive; organic synthesis.
