Isopentane

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Isopentane
Isopentane
Isopentane
IUPAC name 2-Methylbutane
Other names Methylbutane
Identifiers
CAS number [78-78-4]
RTECS number EK4430000
SMILES C(C)CCC
Properties
Molecular formula C5H12
Molar mass 72.15 g/mol
Appearance colorless liquid
Density 0.6 g/ml, liquid
Melting point

−160 °C (113 K)

Boiling point

28 °C (301 K)

Solubility in water Immiscible
Thermochemistry
Std enthalpy of
formation
ΔfHo298
−179 kJ/mol
Std enthalpy of
combustion
ΔcHo298
−3504 kJ/mol
Standard molar
entropy
So298
260.7 J·K−1·mol−1
Hazards
EU classification Highly flammable (F+)
Harmful (Xn)
Dangerous for
the environment (N)
NFPA 704
4
1
0
 
R-phrases R12, R51/53, R65,
R66, R67
S-phrases (S2), S9, S16, S29,
S33, S61, S62
Flash point <−51 °C
Autoignition
temperature
420 °C
Explosive limits 1.4–7.6%
Related compounds
Related alkane Isobutane
Neopentane
2-Methylpentane
Related compounds Pentane
Cyclopentane
Except where noted otherwise, data are given for
materials in their standard state
(at 25 °C, 100 kPa)

Infobox disclaimer and references

Isopentane, C5H12, also called methylbutane or 2-methylbutane, is a branched-chain alkane with five carbon atoms. Isopentane is an extremely volatile and extremely flammable liquid at room temperature and pressure. The normal boiling point is just a few degrees above room temperature and isopentane will readily boil and evaporate away on a warm day. Isopentane is commonly used in conjunction with liquid nitrogen to achieve a liquid bath temperature of -160 °C.

Contents

[edit] Nomenclature

Isopentane is the name recommended by the International Union of Pure and Applied Chemistry (IUPAC) in its 1993 Recommendations for the Nomenclature of Organic Chemistry.[1] It is one of only four acyclic hydrocarbons to retain its pre-IUPAC name.

[edit] Isomers

Isopentane is one of three structural isomers with the molecular formula C5H12, the others being pentane and neopentane.

[edit] References

  1. ^ Panico, R.; & Powell, W. H. (Eds.) (1994). A Guide to IUPAC Nomenclature of Organic Compounds 1993. Oxford: Blackwell Science. ISBN 0-632-03488-2. 

[edit] External links