Neopentane

Neopentane
Names
	Preferred IUPAC name 2,2-Dimethylpropane
	Other names Neopentane; Tetramethylmethane
Identifiers
CAS Number	463-82-1 ;
3D model (JSmol)	Interactive image;
Beilstein Reference	1730722
ChEBI	CHEBI:30358 ;
ChemSpider	9646 ;
ECHA InfoCard	100.006.677
EC Number	207-343-7;
Gmelin Reference	1850
MeSH	neopentane
PubChem CID	10041;
UNII	M863R1J0BP ;
UN number	2044
CompTox Dashboard (EPA)	DTXSID6029179 ;
	InChI InChI=1S/C5H12/c1-5(2,3)4/h1-4H3 Key: CRSOQBOWXPBRES-UHFFFAOYSA-N ;
	SMILES CC(C)(C)C;
Properties
Chemical formula	C5H12
Molar mass	72.151 g·mol−1
Appearance	Colorless gas
Odor	Odorless
Density	3.255 kg/m3 (gas, 9.5 °C); 601.172 kg/m3 (liquid, 9.5 °C)
Melting point	−16.5 °C (2.3 °F; 256.6 K)
Boiling point	9.5 °C (49.1 °F; 282.6 K)
Vapor pressure	146 kPa (at 20 °C)
Henry's law; constant (kH)	4.7 nmol Pa−1 kg−1
Thermochemistry
Heat capacity (C)	121.07–120.57 J K−1 mol−1
Std molar; entropy (S⦵298)	217 J K−1 mol−1
Std enthalpy of; formation (ΔfH⦵298)	−168.5–−167.3 kJ mol−1
Std enthalpy of; combustion (ΔcH⦵298)	−3.51506–−3.51314 MJ mol−1
Hazards
	GHS labelling:
Pictograms
Signal word	Danger
Hazard statements	H220, H411
Precautionary statements	P210, P273, P377, P381, P391, P403, P501
NFPA 704 (fire diamond)	1 4 0
Related compounds
Related alkanes	2,2-Dimethylbutane; 2,3-Dimethylbutane; Triptane; Tetramethylbutane;
Related compounds	Tetramethylsilane; Tetramethylgermane; Tetramethylstannane; Tetramethylplumbane;
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). verify (what is ?) Infobox references

Neopentane, also called 2,2-dimethylpropane, is a double-branched-chain alkane with five carbon atoms. Neopentane is a flammable gas at room temperature and pressure which can condense into a highly volatile liquid on a cold day, in an ice bath, or when compressed to a higher pressure.

Neopentane is the simplest alkane with a quaternary carbon, and has achiral tetrahedral symmetry. It is one of the three structural isomers with the molecular formula C₅H₁₂ (pentanes), the other two being n-pentane and isopentane. Out of these three, it is the only one to be a gas at standard conditions; the others are liquids.

It was first synthesized by Russian chemist Mikhail Lvov in 1870.