Isopentane

{{#if:OdorlessOdorlessColorless liquid616 mg mL⁻¹192 nm76.992 kPa (at 20 °C)7.2 nmol Pa⁻¹ kg⁻¹1.354112114125|! style="background: #F8EABA; text-align: center;" colspan="2" | Properties

Isopentane
IUPAC name 2-Methylbutane
Identifiers
CAS number	78-78-4 Y
PubChem	6556
ChemSpider	6308 Y
UNII	ZH67814I0O Y
EC number	201-142-8
UN number	1265
MeSH	isopentane
ChEBI	CHEBI:30362 Y
RTECS number	EK4430000
Beilstein Reference	1730723
Gmelin Reference	49318
Jmol-3D images	Image 1
SMILES CCC(C)C <p><p style="word-wrap: break-word;">
InChI InChI=1S/C5H12/c1-4-5(2)3/h5H,4H2,1-3H3 Y Key: QWTDNUCVQCZILF-UHFFFAOYSA-N Y
Molecular formula	C5H12
Molar mass	72.15 g mol−1
Thermochemistry
Std enthalpy of formation ΔfHo298	−179.1–−177.3 kJ mol−1
Std enthalpy of combustion ΔcHo298	−3.5052–−3.5036 MJ mol−1
Standard molar entropy So298	260.41 J K−1 mol−1
Specific heat capacity, C	164.85 J K−1 mol−1
Hazards
GHS pictograms
GHS signal word	DANGER
GHS hazard statements	H224, H304, H336, H411
GHS precautionary statements	P210, P261, P273, P301+310, P331
EU Index	601-006-00-1
EU classification	F+ Xn N
R-phrases	R12, R51/53, R65, R66, R67
S-phrases	(S2), S16, S29, S33
NFPA 704	4 1 0
Flash point	−51 °C
Autoignition temperature	420 °C
Explosive limits	1.4–8.3%
Related compounds
Related alkanes	Isobutane 2-Methylpentane 3-Methylpentane 3-Ethylpentane
Related compounds	2-Ethyl-1-butanol
Y (verify) (what is: Y/N?) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox 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. It is 1% or less of natural gas.

Nomenclature

Isopentane is the name recommended by the International Union of Pure and Applied Chemistry (IUPAC). An isopentyl group is a subset of the generic pentyl group. It has the chemical structure -CH₂CH₂CH(CH₃)₂.

Isomers

Isopentane is one of three structural isomers with the molecular formula C₅H₁₂, the others being pentane (n-pentane) and neopentane (dimethyl propane).

Uses

Isopentane is one of the ingredients in both Aquafresh and Sensodyne.

External links

• International Chemical Safety Card 1153
• IUPAC Nomenclature of Organic Chemistry (online version of the "Blue Book")

cs:Isopentan