Isopentane
Names | |
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Preferred IUPAC name
2-Methylbutane[1] | |
Other names
Isopentane
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Identifiers | |
3D model (
JSmol ) |
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1730723 | |
ChEBI | |
ChemSpider | |
ECHA InfoCard
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100.001.039 |
EC Number |
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49318 | |
MeSH | isopentane |
PubChem CID
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RTECS number
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UNII | |
UN number | 1265 |
CompTox Dashboard (EPA)
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Properties | |
C5H12 | |
Molar mass | 72.151 g·mol−1 |
Appearance | Colorless liquid |
Odor | Gasoline-like |
Density | 616 mg mL−1[2] |
Melting point | −161 to −159 °C; −258 to −254 °F; 112 to 114 K |
Boiling point | 27.8 to 28.2 °C; 81.9 to 82.7 °F; 300.9 to 301.3 K |
Vapor pressure | 76.992 kPa (at 20 °C) |
Henry's law
constant (kH) |
7.2 nmol Pa−1 kg−1 |
UV-vis (λmax) | 192 nm |
Refractive index (nD)
|
1.354 |
Viscosity | 0.214 cP (at 20 °C) |
Thermochemistry | |
Heat capacity (C)
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164.85 J K−1 mol−1 |
Std molar
entropy (S⦵298) |
260.41 J K−1 mol−1 |
Std enthalpy of (ΔfH⦵298)formation |
−179.1–−177.3 kJ mol−1 |
Std enthalpy of (ΔcH⦵298)combustion |
~ 3.3 MJ mol−1, 19,664 Btu/lb |
Hazards | |
GHS labelling: | |
Danger | |
H224, H301, H302, H305, H336, H411 | |
P210, P261, P273, P301+P310, P331 | |
NFPA 704 (fire diamond) | |
Flash point | −51 °C (−60 °F; 222 K) |
420 °C (788 °F; 693 K) | |
Explosive limits
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1.4–8.3% |
Related compounds | |
Related alkanes
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Related compounds
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2-Ethyl-1-butanol |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Isopentane, also called methylbutane or 2-methylbutane, is a branched-chain saturated hydrocarbon (an alkane) with five carbon atoms, with formula C
5H
12 or CH(CH
3)
2(C
2H
5).
Isopentane is a
Isopentane is commonly used in conjunction with liquid nitrogen to achieve a liquid bath temperature of −160 °C. Natural gas typically contains 1% or less isopentane,[3] but it is a significant component of natural gasoline.[4]
Nomenclature
The traditional name isopentane was still retained in the 1993 IUPAC recommendations,[5][6] but is no longer recommended according to the 2013 recommendations.[1] The preferred IUPAC name is the systematic name 2-methylbutane. An isopentyl group is a subset of the generic pentyl group. It has the chemical structure -CH3CH2CH(CH3)2.
Uses
Isopentane is used in a closed loop in geothermal power production to drive turbines.[7]
Isopentane is used, in conjunction with
Isopentane is a major component (sometimes 30% or more) of natural gasoline, an analog of common petroleum-derived gasoline that is condensed from natural gas.[4] It has a substantially higher octane rating (RON 93.7) than n-pentane (61.7), and therefore there is interest in conversion from the latter.[9]
References
- ^ ISBN 978-0-85404-182-4.
The names 'isobutane', 'isopentane' and 'neopentane' are no longer recommended.
- ^ a b Ivan F. Avery, L. V. Harvey (1958): Natural-gasoline and Cycling Plants in the United States, Information circular, U.S. Department of the Interior, Bureau of Mines. 12 pages.
- ^ Table 19(a) Acyclic and monocyclic hydrocarbons. Parent hydrocarbons
- ISBN 0-632-03488-2.
- ^ Byproduct Isopentane also used in some of the LPG plant to run the boiler and generate the power. HS Orka HF Energy Plant IV Archived 2014-10-18 at the Wayback Machine
- ^ "Animal Resources Program - the Office of the Vice President for Research | UAB".
External links
- International Chemical Safety Card 1153
- IUPAC Nomenclature of Organic Chemistry (online version of the "Blue Book")