Difference between revisions of "Butane" - New World Encyclopedia
| Line 33: | Line 33: | ||
'''Butane''', also called '''''n''-butane''', is the unbranched [[alkane]] with four [[carbon]] [[atom]]s, CH<sub>3</sub>CH<sub>2</sub>CH<sub>2</sub>CH<sub>3</sub>. ''Butane'' is also used as a collective term for both ''n''-butane together and its only other [[isomer]], [[isobutane]] (also called ''i''-butane or methylpropane), CH(CH<sub>3</sub>)<sub>3</sub>. | '''Butane''', also called '''''n''-butane''', is the unbranched [[alkane]] with four [[carbon]] [[atom]]s, CH<sub>3</sub>CH<sub>2</sub>CH<sub>2</sub>CH<sub>3</sub>. ''Butane'' is also used as a collective term for both ''n''-butane together and its only other [[isomer]], [[isobutane]] (also called ''i''-butane or methylpropane), CH(CH<sub>3</sub>)<sub>3</sub>. | ||
| − | Both isomers of butane are highly flammable, colorless [[gas]]es that can be easily [[liquefy|liquefied]]. The name butane was derived by back-formation from the name | + | Both isomers of butane are highly flammable, colorless [[gas]]es that can be easily [[liquefy|liquefied]]. |
| + | |||
| + | |||
| + | Butane gas is sold bottled as a fuel for cooking and camping. When blended with [[propane]] and other hydrocarbons, it is referred to commercially as [[Liquified petroleum gas]] (LPG). It is also used as a component of [[gasoline]] (petrol), 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. | ||
| + | |||
| + | Highly purified forms of butane, especially isobutane, can be used as [[refrigerant]]s. They are used, for instance, in household refrigerators and freezers, largely replacing the [[halomethane]]s that are believed to deplete the [[ozone layer]]. The flammability of butane is not a major issue because the amount of butane in an appliance is not enough to cause a combustible mix, given the amount of air in a room. The system operating pressure for butane is lower than that for the halomethanes, such as [[Dichlorodifluoromethane]] (R-12). Thus, the direct conversion of R-12 systems to butane, such as in automotive air conditioning systems, will not function optimally. | ||
| + | |||
| + | == Etymology == | ||
| + | |||
| + | The name butane was derived by back-formation from the name [[butyric acid]]. The latter is a [[carboxylic acid]] with four carbon atoms, including the carbon atom in the carboxyl group. | ||
== Properties == | == Properties == | ||
Revision as of 18:11, 20 May 2008
| Butane | |
|---|---|
| |
| |
| Identifiers | |
| CAS number | [] |
| SMILES | CCCC |
| Properties | |
| Molecular formula | C4H10 |
| Molar mass | 58.14 g/mol |
| Appearance | Colorless gas |
| Density | 2.48 g/l, gas (15 °C, 1 atm) |
| Melting point |
−138 °C (135 K) |
| Boiling point |
−0.5 °C (272.6 K) |
| Solubility in water | 6.1 mg/100 ml (20 °C) |
| Hazards | |
| EU classification | Highly flammable (F+) |
| NFPA 704 |
4
1
0
|
| Flash point | −60 °C |
| 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) | |
Butane, also called n-butane, is the unbranched alkane with four carbon atoms, CH3CH2CH2CH3. Butane is also used as a collective term for both n-butane together and its only other isomer, isobutane (also called i-butane or methylpropane), CH(CH3)3.
Both isomers of butane are highly flammable, colorless gases that can be easily liquefied.
Butane gas is sold bottled as a fuel for cooking and camping. When blended with propane and other hydrocarbons, it is referred to commercially as Liquified petroleum gas (LPG). It is also used as a component of gasoline (petrol), as a feedstock for the production of base petrochemicals in steam cracking, as fuel for cigarette lighters, and as a propellant in aerosol sprays.
Highly purified forms of butane, especially isobutane, can be used as refrigerants. They are used, for instance, in household refrigerators and freezers, largely replacing the halomethanes that are believed to deplete the ozone layer. The flammability of butane is not a major issue because the amount of butane in an appliance is not enough to cause a combustible mix, given the amount of air in a room. The system operating pressure for butane is lower than that for the halomethanes, such as Dichlorodifluoromethane (R-12). Thus, the direct conversion of R-12 systems to butane, such as in automotive air conditioning systems, will not function optimally.
Etymology
The name butane was derived by back-formation from the name butyric acid. The latter is a carboxylic acid with four carbon atoms, including the carbon atom in the carboxyl group.
Properties
At ordinary temperatures and pressures, n-butane is a colorless gas. Its boiling point is −0.5 °C (272.6 K), and its melting point is −138.4 °C (135.4 K).
As noted above, the term butane is also used for i-butane, the structural isomer of n-butane. i-butane is also a colorless gas, with a boiling point of -11.7 °C (261 K) and a melting point of -159.6 °C (114 K).
Structural isomers
A molecule of either isomer, n-butane or i-butane, is made up of four carbon atoms and ten hydrogen atoms, so their common molecular formula is C4H10. However, the molecular structures of these isomers differ. In particular, a molecule of n-butane consists of a linear arrangement of the four carbon atoms, so that it can also be represented as CH3-CH2-CH2-CH3. By contrast, a molecule of i-butane has three carbon atoms attached directly to a central carbon atom. The structures of these two isomers are shown in the diagrams below.
- Structures of the two isomers of butane
n-Butane
i-Butane
Reactions
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. The reaction may be written as follows:
- 2C4H10 + 13O2 → 8CO2 + 10H2O
n-Butane is the feedstock for DuPont's catalytic process for the preparation of maleic anhydride (C2H2(CO)2O), as shown by the following reaction:
- CH3CH2CH2CH3 + 3.5O2 → C2H2(CO)2O + 4H2O
n-Butane, like all hydrocarbons, undergoes free radical chlorination producing both 1-chlorobutane and 2-chlorobutane, as well as more highly chlorinated derivatives.
Uses
Butane gas is sold bottled as a fuel for cooking and camping. When blended with propane and other hydrocarbons, it is referred to commercially as Liquified petroleum gas (LPG). It is also used as a component of gasoline (petrol), as a feedstock for the production of base petrochemicals in steam cracking, as fuel for cigarette lighters, and as a propellant in aerosol sprays.
Highly purified forms of butane, especially isobutane, can be used as refrigerants. They are used, for instance, in household refrigerators and freezers, largely replacing the halomethanes that are believed to deplete the ozone layer. The flammability of butane is not a major issue because the amount of butane in an appliance is not enough to cause a combustible mix, given the amount of air in a room. The system operating pressure for butane is lower than that for the halomethanes, such as Dichlorodifluoromethane (R-12). Thus, the direct conversion of R-12 systems to butane, such as in automotive air conditioning systems, will not function optimally.
Effects and health issues
Inhaling butane can cause drowsiness, narcosis, asphyxia; cardiac arrhythmia and frostbite, which can result in instant death from Asphyxiation, Acute toxicity and ventricular fibrillation. Butane is the most commonly misused volatile solvent in the UK, and was the cause of 52 percent of solvent-related deaths in 2000.[1] If butane is sprayed directly into the throat, the jet of fluid may cool rapidly to –20 °C by expansion, causing prolonged laryngospasm.[2] "Sudden Sniffer's Death syndrome," first described by Bass in 1970,[3] is the most common single cause of solvent-related death, resulting in 55 percent of known fatal cases.[2]
See also
Notes
- ↑ Field-Smith, M.E., B.K. Butland, J.D. Ramsey, and H.R. Anderson. July 2006. Trends in Death Associated with Abuse of Volatile Substances 1971-2004. Report 19, Division of Community Health Sciences. London: St George’s, University of London. Retrieved May 20, 2008.
- ↑ 2.0 2.1 Ramsey, J., H.R. Anderson, K. Bloor, et al. 1989. An introduction to the practice, prevalence and chemical toxicology of volatile substance abuse. Hum. Toxicol. 8:261–269.
- ↑ Bass, M. 1970. Sudden sniffing death. JAMA 212:2075–79.
ReferencesISBN links support NWE through referral fees
- McMurry, John. 2004. Organic Chemistry, 6th ed. Belmont, CA: Brooks/Cole. ISBN 0534420052.
- Morrison, Robert T., and Robert N. Boyd. 1992. Organic Chemistry, 6th ed. Englewood Cliffs, NJ: Prentice Hall. ISBN 0136436692.
- Solomons, T.W. Graham, and Craig B. Fryhle 2004. Organic Chemistry, 8th ed. Hoboken, NJ: John Wiley. ISBN 0471417998.
- Yaws, Carl L. 2005. The Yaws Handbook of Physical Properties for Hydrocarbons and Chemicals: Physical Properties for More Than 41,000 Organic and Inorganic Chemical Compounds : Coverage for C1 to C100 Organics and Ac to Zr Inorganics. Houston, TX: Gulf Pub. Co. ISBN 978-0976511373.
External links
All links retrieved November 8, 2007.
- International Chemical Safety Card 0232
- NIOSH Pocket Guide to Chemical Hazards
- European Chemicals Bureau
- n-Butane Molecule of the Month
- Molview from bluerhinos.co.uk See Butane in 3D
- Computational Chemistry Wiki
- World LP Gas Association (WLPGA)
- LP Gas Association: Propane and Butane in the UK
- Global BioSciences In-Situ Bioremediation utilizing Butane
- Butane Viscosity as tunction of temperature and pressure
| Alkanes | |||||||||||||||||||||||||||||||
|
methane |
| |
ethane |
| |
propane |
| |
butane |
| |
pentane |
| |
hexane |
|||||||||||||||||||||
|
heptane |
| |
octane |
| |
nonane |
| |
decane |
| |
undecane |
| |
dodecane |
| ||||||||||||||||||||
E numbers
| ||
|---|---|---|
| Colours (E100-199) • Preservatives (E200-299) • Antioxidants & Acidity regulators (E300-399) • Thickeners, stabilisers & emulsifiers (E400-499) • pH regulators & anti-caking agents (E500-599) • Flavour enhancers (E600-699) • Miscellaneous (E900-999) • Additional chemicals (E1100-1599) | ||
| Waxes (E900-909) • Synthetic glazes (E910-919) • Improving agents (E920-929) • Packaging gases (E930-949) • Sweeteners (E950-969) • Foaming agents (E990-999) | ||
| Argon (E938) • Helium (E939) • Dichlorodifluoromethane (E940) • Nitrogen (E941) • Nitrous oxide (E942) • Butane (E943a) • Isobutane (E943b) • Propane (E944) • Oxygen (E948) • Hydrogen (E949) | ||
Credits
New World Encyclopedia writers and editors rewrote and completed the Wikipedia article in accordance with New World Encyclopedia standards. This article abides by terms of the Creative Commons CC-by-sa 3.0 License (CC-by-sa), which may be used and disseminated with proper attribution. Credit is due under the terms of this license that can reference both the New World Encyclopedia contributors and the selfless volunteer contributors of the Wikimedia Foundation. To cite this article click here for a list of acceptable citing formats.The history of earlier contributions by wikipedians is accessible to researchers here:
The history of this article since it was imported to New World Encyclopedia:
Note: Some restrictions may apply to use of individual images which are separately licensed.
