Butane

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Butane
Butane.jpg
Liquid butane
Names
IUPAC name
Butane
Other names
Butyl hydride
Methylethylmethane
Quartane
Properties
C4H10
Molar mass 58.12 g/mol
Appearance Colorless gas
Odor Gas-like
Density 2.48 g/cm3 (at 15 °C)
Melting point −0.5 °C (31.1 °F; 272.6 K)
Boiling point −138.3 °C (−216.9 °F; 134.8 K)
0.61 g/100 ml (at 20 °C)
Solubility Soluble in chloroform, diethyl ether, ethanol, THF
Vapor pressure ~170 kPa at 10 °C
Thermochemistry
−126.3 – −124.9 kJ/mol
Hazards
Safety data sheet Sigma-Aldrich
Flash point −60 °C (−76 °F; 213 K)
Related compounds
Related compounds
Propane
Pentane
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Butane is an organic compound, with the chemical formula C4H10. It consists of two structural isomers, n-butane and isobutane, also known as methylpropane.

Properties

Chemical

Both butane isomers react with halogens to yield halobutanes in the presence of UV light. Iodine however does not react with butane, instead it dissolves in it.

Butane burns in air to produce carbon dioxide and water vapor.

C4H10 + 13/2 O2 → 4 CO2 + 5 H2O

Physical

Butane is a gas at standard conditions, easily compressible. Butane consists of two isomers:

  • n-Butane: A colorless gas at standard conditions, n-butane melts at −138 °C and boils at -0.5°C. Its density is 0.579 g/mL at 20 °C. The flash point of n-butane is 45 °C.
  • Isobutane: Just like the n isomer, isobutane is a colorless gas. It melts at −160 °C and boils at −12 °C.

The solubility of butane in various organic solvents depends strongly on temperature and type of solvent. Some solvents, such as xylene appears to be miscible with butane.

Availability

Camping fire stove tanks contain a mixture of isobutane with propane, usually in a 80:20 ratio.

If pure butane is desired, you can buy it from gas companies, if they're willing to sell it to individuals.

Preparation

N-butane can be prepared by decarboxylating valeric acid salts.

Projects

Handling

Safety

Butane has low toxicity, but in high concentration can cause asphyxiation. It is very flammable and in closed chambers may form explosive mixtures with air, though since butane is heavier than air, it will mostly build-up in the lower parts of the room.

Storage

Butane tanks should be stored in cold places.

Disposal

Butane can be safely released in open air or burned. Do not release it in closed chambers, as being flammable will form explosive mixtures with air.

References

Relevant Sciencemadness threads