Propane
Propane (/ˈproʊpeɪn/) is a three-carbon alkane with the molecular formula C3H8. It is a gas at standard temperature and pressure, but compressible to a transportable liquid. A by-product of natural gas processing and petroleum refining, it is commonly used as a fuel in domestic and industrial applications and in low-emissions public transportation. Discovered in 1857 by the French chemist Marcellin Berthelot, it became commercially available in the US by 1911. Propane is one of a group of liquefied petroleum gases (LP gases). The others include butane, propylene, butadiene, butylene, isobutylene, and mixtures thereof. Propane has lower volumetric energy density, but higher gravimetric energy density and burns more cleanly than gasoline and coal.[6]
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| Names | |||
|---|---|---|---|
| Preferred IUPAC name
Propane[1] | |||
| Systematic IUPAC name
Tricarbane (never recommended[1]) | |||
| Identifiers | |||
3D model (JSmol) |
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| 1730718 | |||
| ChEBI | |||
| ChEMBL | |||
| ChemSpider | |||
| ECHA InfoCard | 100.000.753 | ||
| EC Number |
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| E number | E944 (glazing agents, ...) | ||
| 25044 | |||
| KEGG | |||
PubChem CID |
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| RTECS number |
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| UNII | |||
| UN number | 1978 | ||
CompTox Dashboard (EPA) |
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| Properties[2] | |||
| C3H8 | |||
| Molar mass | 44.097 g·mol−1 | ||
| Appearance | Colorless gas | ||
| Odor | Odorless | ||
| Density | 2.0098 kg/m3 (at 0 °C, 101.3 kPa) | ||
| Melting point | −187.7 °C; −305.8 °F; 85.5 K | ||
| Boiling point | −42.25 to −42.04 °C; −44.05 to −43.67 °F; 230.90 to 231.11 K | ||
| 47 mg⋅L−1 (at 0 °C) | |||
| log P | 2.236 | ||
| Vapor pressure | 853.16 kPa (at 21.1 °C (70.0 °F)) | ||
Henry's law constant (kH) |
15 nmol⋅Pa−1⋅kg−1 | ||
| Conjugate acid | Propanium | ||
| −40.5 × 10−6 cm3/mol | |||
| 0.083 D[3] | |||
| Thermochemistry | |||
Heat capacity (C) |
73.60 J⋅K−1⋅mol−1 | ||
Std enthalpy of formation (ΔfH⦵298) |
−105.2–104.2 kJ⋅mol−1 | ||
Std enthalpy of combustion (ΔcH⦵298) |
−2.2197–2.2187 MJ⋅mol−1 | ||
| Hazards | |||
| GHS labelling: | |||
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| Danger | |||
| H220 | |||
| P210 | |||
| NFPA 704 (fire diamond) | |||
| Flash point | −104 °C (−155 °F; 169 K) | ||
| 470 °C (878 °F; 743 K) | |||
| Explosive limits | 2.37–9.5% | ||
| NIOSH (US health exposure limits): | |||
PEL (Permissible) |
TWA 1,000 ppm (1,800 mg/m3)[4] | ||
REL (Recommended) |
TWA 1,000 ppm (1,800 mg/m3)[4] | ||
IDLH (Immediate danger) |
2,100 ppm[4] | ||
| Related compounds | |||
Related alkanes |
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Related compounds |
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| Supplementary data page | |||
| Propane (data page) | |||
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Propane gas has become a popular choice for barbecues and portable stoves because its low −42 °C boiling point makes it vaporise inside pressurised liquid containers (2 phases). Propane powers buses, forklifts, taxis, outboard boat motors, and ice resurfacing machines and is used for heat and cooking in recreational vehicles and campers.