ABSTRACT
CH3 CASRN: 565-59-3; DOT: 1993; DOT label: flammable liquid; molecular formula: C7H16; FW: 100.20 Physical state and color: Clear, colorless, flammable liquid with an odor resembling hexane. An odor threshold concentration of 4.5 ppmv was reported by Nagata and Takeuchi (1990). Boiling point (°C): 89.8 (Weast, 1986) Density (g/cm3): 0.6951 at 20 °C (Weast, 1986) 0.69080 at 25.00 °C (Bouzas et al., 2000) Diffusivity in water (x 10-5 cm2/sec): 0.71 at 20 °C using method of Hayduk and Laudie (1974) Dissociation constant, pKa: >14 (Schwarzenbach et al., 1993) Flash point (°C): -6 (Aldrich, 1990) Lower explosive limit (%): 1.1 (NFPA, 1984) Upper explosive limit (%): 6.7 (NFPA, 1984) Heat of fusion (kcal/mol): 1.389 (Dreisbach, 1959) Henry’s law constant (atm⋅m3/mol): 1.72 at 25 °C (Mackay and Shiu, 1981) Interfacial tension with water (dyn/cm): 49.6 at 25 °C (quoted, Freitas et al., 1997) Soil organic carbon/water partition coefficient, log Koc: Unavailable because experimental methods for estimation of this parameter for aliphatic hydrocarbons are lacking in the documented literature Octanol/water partition coefficient, log Kow: 3.26 using method of Hansch et al. (1968)
Soluble in acetone, alcohol, benzene, chloroform, and ether (Weast, 1986) Solubility in water: 5.25 mg/kg at 25 °C (shake flask-GLC, Price, 1976) Vapor density: 4.10 g/L at 25 °C, 3.46 (air = 1) Vapor pressure (mmHg): 68.9 at 25 °C (Wilhoit and Zwolinski, 1971) 24.937 at 4.999 °C (inclined-piston, Osborn and Douslin, 1974) Environmental fate: Photolytic. A photooxidation rate constant of 3.4 x 10-12 cm3/molecule⋅sec was reported for the gas-phase reaction of 2,3-dimethylpentane and OH radicals (Atkinson, 1990). Chemical/Physical. Complete combustion in air yields carbon dioxide and water vapor. 2,3Dimethylpentane will not hydrolyze because it has no hydrolyzable functional group. Source: In diesel engine exhaust at a concentration of 0.9% of emitted hydrocarbons (quoted, Verschueren, 1983). Schauer et al. (1999) reported 2,3-dimethylpentane in a diesel-powered medium-duty truck exhaust at an emission rate of 720 µg/km. California Phase II reformulated gasoline contained 2,3-dimethylpentane at a concentration of 29.4 g/kg. Gas-phase tailpipe emission rates from gasoline-powered automobiles with and without catalytic converters were 5.34 and 714 mg/km, respectively (Schauer et al., 2002). Uses: Organic synthesis; gasoline component.
