Butane: Difference between revisions
→Reactions and uses: Cleaned up R-12 replacement & halomethane ref. |
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::CH<sub>3</sub>CH<sub>2</sub>CH<sub>2</sub>CH<sub>3</sub> + 3.5 O<sub>2</sub> → C<sub>2</sub>H<sub>2</sub>(CO)<sub>2</sub>O + 4 H<sub>2</sub>O |
::CH<sub>3</sub>CH<sub>2</sub>CH<sub>2</sub>CH<sub>3</sub> + 3.5 O<sub>2</sub> → C<sub>2</sub>H<sub>2</sub>(CO)<sub>2</sub>O + 4 H<sub>2</sub>O |
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Butane, like all hydrocarbons, undergoes [[free radical]] chlorination to give both 1-chloro- and 2-chlorobutanes, as well as more highly chlorinated derivatives. The relative rates of the chlorination is partially explained by the differing [[bond dissociation energies]], 425 and 411 |
Butane, like all hydrocarbons, undergoes [[free radical]] chlorination to give both 1-chloro- and 2-chlorobutanes, as well as more highly chlorinated derivatives. The relative rates of the chlorination is partially explained by the differing [[bond dissociation energies]], 425 and 411 [[joule|kJ]]/mol for the two types of C-H bonds. The two central carbon atoms have the slightly weaker C-H bonds. <!--I hope this is right--> |
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Butane gas is sold bottled as a fuel for cooking and camping, in which case it is referred to commercially as [[Liquified petroleum gas|LPG]]. It is also used as a petrol component, as a feedstock for the production of base petrochemicals in steam cracking, as fuel for [[cigarette lighter]]s and as a [[propellant]] in [[aerosol spray]]s. Despite its flammability, very pure forms of butane are also occasionally used as a [[Liquified petroleum gas#LPG as refrigerant|refrigerant]] in automobiles that are set up to use [[Dichlorodifluoromethane|R-12]], because R-12 is an [[ozone]] depleting [[halomethane]]. |
Butane gas is sold bottled as a fuel for cooking and camping, in which case it is referred to commercially as [[Liquified petroleum gas|LPG]]. It is also used as a petrol component, as a feedstock for the production of base petrochemicals in steam cracking, as fuel for [[cigarette lighter]]s and as a [[propellant]] in [[aerosol spray]]s. Despite its flammability, very pure forms of butane are also occasionally used as a [[Liquified petroleum gas#LPG as refrigerant|refrigerant]] in automobiles that are set up to use [[Dichlorodifluoromethane|R-12]], because R-12 is an [[ozone]] depleting [[halomethane]]. |
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Revision as of 02:52, 6 July 2006
| Butane | |||||
|---|---|---|---|---|---|
 
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| General | |||||
| Molecular formula | C4H10 | ||||
| SMILES | CCCC | ||||
| Molar mass | 58.08 g/mol | ||||
| Appearance | colorless gas | ||||
| CAS number | [106-97-8] | ||||
| Properties | |||||
| Density and phase | 2.52 g/l, gas (15 °C, 1 atm) | ||||
| Solubility in water | 6.1 mg/100 ml (20 °C) | ||||
| Melting point | −138.3 °C (134.9 K) | ||||
| Boiling point | −0.5 °C (272.7 K) | ||||
| Hazards | |||||
| MSDS | External MSDS | ||||
| EU classification | Highly flammable (F+) | ||||
| NFPA 704 |
| ||||
| R-phrases | Template:R12 | ||||
| S-phrases | Template:S2, Template:S9, Template:S16 | ||||
| Flash point | −60 °C | ||||
| Autoignition temperature | 287 °C | ||||
| Explosive limits | 1.8–8.4% | ||||
| Supplementary data page | |||||
| Structure and properties |
n, εr, etc. | ||||
| Thermodynamic data |
Phase behaviour Solid, liquid, gas | ||||
| Spectral data | UV, IR, NMR, MS | ||||
| Related compounds | |||||
| Related alkanes | Propane Pentane | ||||
| Related compounds | Isobutane | ||||
| Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox disclaimer and references | |||||
Butane, also called n-butane, is the unbranched alkane with four carbon atoms, CH3CH2CH2CH3. Butane is also used as a collective term for n-butane together with its only other isomer, isobutane (also called methylpropane), CH(CH3)3.
Butanes are highly flammable, colorless, easily liquefied gases. The name butane was derived by back-formation from the name of butyric acid.
Reactions and uses
When oxygen is plentiful, butane burns to form carbon dioxide and water vapor: When oxygen is limited, carbon (soot) or carbon monoxide may also be formed.
n-Butane is the feedstock for duPont's process for the preparation of maleic anhydride. The catalyst for this process has the approximate formula
- CH3CH2CH2CH3 + 3.5 O2 → C2H2(CO)2O + 4 H2O
Butane, like all hydrocarbons, undergoes free radical chlorination to give both 1-chloro- and 2-chlorobutanes, as well as more highly chlorinated derivatives. The relative rates of the chlorination is partially explained by the differing bond dissociation energies, 425 and 411 kJ/mol for the two types of C-H bonds. The two central carbon atoms have the slightly weaker C-H bonds.
Butane gas is sold bottled as a fuel for cooking and camping, in which case it is referred to commercially as LPG. It is also used as a petrol component, as a feedstock for the production of base petrochemicals in steam cracking, as fuel for cigarette lighters and as a propellant in aerosol sprays. Despite its flammability, very pure forms of butane are also occasionally used as a refrigerant in automobiles that are set up to use R-12, because R-12 is an ozone depleting halomethane.
See also
References
Bond dissociation energies: Senosiain, J. P.; Han, J. H.; Musgrave, C. B.; Golden, D. M. Faraday Discussions (2001), vol. 119, 173-189 Coulston, G. W.; Bare, S. R.; Kung, H.; Birkeland, K.; Bethke, G. K.; Harlow, R.; Herron, N.; Lee, P. L. "The Kinetic Significance of V5+ in n-Butane Oxidation Catalyzed by Vanadium Phosphates" Science (1997) Vol. 275, pp. 191 - 193.