Heptane

Heptane
Names
	Preferred IUPAC name Heptane
	Other names Septane
Identifiers
CAS Number	142-82-5 ;
3D model (JSmol)	Interactive image;
Beilstein Reference	1730763
ChEBI	CHEBI:43098 ;
ChEMBL	ChEMBL134658 ;
ChemSpider	8560 ;
EC Number	205-563-8;
Gmelin Reference	49760
MeSH	n-heptane
PubChem CID	8900;
RTECS number	MI7700000;
UNII	456148SDMJ ;
UN number	1206
	InChI InChI=1S/C7H16/c1-3-5-7-6-4-2/h3-7H2,1-2H3 Key: IMNFDUFMRHMDMM-UHFFFAOYSA-N ;
	SMILES CCCCCCC;
Properties
Chemical formula	C7H16
Molar mass	100.205 g·mol−1
Appearance	Colourless liquid
Odor	Petrolic
Density	0.6795 g⋅cm−3
Melting point	−90.549 °C (−130.988 °F; 182.601 K)
Boiling point	98.38 °C (209.08 °F; 371.53 K)
Solubility in water	insoluble
log P	4.66
Vapor pressure	5.33 kPa (0.773 psi) (20 °C (68 °F; 293 K))
Henry's law; constant (kH)	12 nmol/(Pa·kg)
Magnetic susceptibility (χ)	−85.24×10−6 cm3/mol
Refractive index (nD)	1.3855
Viscosity	0.389 mPa·s
Thermochemistry
Heat capacity (C)	224.64 J⋅mol−1·K-1
Std molar; entropy (S⦵298)	328.57 J⋅mol−1·K-1
Std enthalpy of; formation (ΔfH⦵298)	−225.2 to −223.6 kJ⋅mol−1
Std enthalpy of; combustion (ΔcH⦵298)	−4.825 to −4.809 MJ⋅mol−1
Hazards
	GHS labelling:
Pictograms
Signal word	Danger
Hazard statements	H225, H304, H315, H336, H410
Precautionary statements	P210, P233, P240, P241, P242, P243, P261, P264, P271, P273, P280, P301+P310, P303+P361+P353, P304+P340+P312, P331, P332+P313, P362, P370+P378, P391, P403+P233, P403+P235, P405, P501
NFPA 704 (fire diamond)	3 3 0
Flash point	−4 °C (25 °F; 269 K)
Autoignition; temperature	215 °C (419 °F; 488 K)
Explosive limits	1.05%–6.7%
Threshold limit value (TLV)	200 ppm (TWA), 400 ppm (STEL)
	Lethal dose or concentration (LD, LC):
LD50 (median dose)	>2000 mg/kg (rat, oral); 3000 mg/kg (rabbit, dermal);
LC50 (median concentration)	17,986 ppm (mouse, 2 hr)
LCLo (lowest published)	16,000 ppm (human); 15,000 ppm (mouse, 30 min);
	NIOSH (US health exposure limits):
PEL (Permissible)	TWA 500 ppm (2000 mg/m3)
REL (Recommended)	TWA 85 ppm (350 mg/m3); C 440 ppm (1800 mg/m3, 15 minute);
IDLH (Immediate danger)	750 ppm
Related compounds
Related alkanes	Hexane; Octane;
	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

Heptane or n-heptane is the straight-chain alkane with the chemical formula H₃C(CH₂)₅CH₃ or C₇H₁₆. When used as a test fuel component in anti-knock test engines, a 100% heptane fuel is the zero point of the octane rating scale (the 100 point is 100% iso-octane). Octane number equates to the anti-knock qualities of a comparison mixture of heptane and iso-octane which is expressed as the percentage of iso-octane in heptane, and is listed on pumps for gasoline (petrol) dispensed globally.