Title: Propane
CAS Registry Number: 74-98-6
Additional Names: Dimethylmethane; propyl hydride
Molecular Formula: C3H8
Molecular Weight: 44.10
Percent Composition: C 81.71%, H 18.28%
Line Formula: CH3CH2CH3
Literature References: Constituent of natural gas and of crude petroleum. Obtained by the so-called "stabilization process" using fractional distillation under pressure: Francis, Robbins, J. Am. Chem. Soc. 55, 4339 (1933). Many syntheses, e.g., by using butyronitrile and sodium: Timmermans, J. Chim. Phys. 18, 133 (1920).
Properties: Gas. Odorless when pure. Burns with a luminous, smoky flame. Explosive limits, % by vol in air: 2.37-9.5. Heavier than air. One liter weighs 2.0200 g at 0° and 760 mm; 1.8324 g at 25° and 760 mm. Liquefies at -42°; solid at -187.7°. bp (1 atm) -42.1°; bp (2 atm) -25.6°; bp (5 atm) 1.4°; bp (10 atm) 26.9°; bp (20 atm) 58.1°; bp (30 atm) 78.7°; bp (40 atm) 94.8°. Crit temp 96.81°; crit press. 42.01 atm. Heat of combustion (const vol) 528.4 cal, (const pressure) 553.5 cal. 100 vols water dissolve 6.5 vols at 17.8° and 753 mm pressure; 100 vols abs alc dissolve 790 vols at 16.6° and 754 mm pressure; 100 vols ether dissolve 926 vols at 16.6° and 757 mm pressure; 100 vols chloroform dissolve 1299 vols at 21.6° and 757 mm pressure; 100 vols benzene dissolve 1452 vols at 21.5° and 757 mm pressure; 100 vols turpentine dissolve 1587 vols at 17.7° and 757 mm pressure.
Boiling point: bp (1 atm) -42.1°; bp (2 atm) -25.6°; bp (5 atm) 1.4°; bp (10 atm) 26.9°; bp (20 atm) 58.1°; bp (30 atm) 78.7°; bp (40 atm) 94.8°
CAUTION: Potential symptoms of overexposure are dizziness, confusion, excitation, asphyxia; direct contact with liquid may cause frostbite. See NIOSH Pocket Guide to Chemical Hazards (DHHS/NIOSH 97-140, 1997) p 262.
Use: As fuel gas, sometimes mixed with butane. In organic syntheses. As refrigerant. |