Editing Octane (section)

{{Short description|Hydrocarbon compound with the formula C8H18}}
{{Distinguish|octene|octyne}}
{{for-multi|the gasoline rating system|Octane rating|other uses}} {{Chembox
| ImageFile      = Octane-2D-Skeletal.svg
| ImageClass = skin-invert-image
| ImageFile1     = OctaneFull.png
| ImageClass1 = skin-invert-image
| ImageFile2     = Octane 3D ball.png
| ImageClass2 = bg-transparent
| ImageFile3     = N-octane-spaceFilling.png
| ImageClass3 = bg-transparent
| ImageAlt       = Skeletal formula of octane
| ImageFile_Ref  = {{chemboximage|correct|??}}
| ImageAlt1      = Skeletal formula of octane with all implicit carbons shown, and all explicit hydrogens added
| ImageFile1_Ref = {{chemboximage|correct|??}}
| ImageAlt2      = Ball-and-stick model of octane
| ImageFile2_Ref = {{chemboximage|correct|??}}
| ImageSize3     = 160
| ImageAlt3      = Space-filling model of octane
| ImageFile3_Ref = {{chemboximage|correct|??}}
| OtherNames     = ''n''-Octane
| SystematicName = Octane<ref>{{Cite web|title=octane - Compound Summary|url=https://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?cid=356&loc=ec_rcs|work=PubChem Compound|publisher=National Center for Biotechnology Information|access-date=6 January 2012|location=USA|date=16 September 2004|at=Identification and Related Records}}</ref>
| Section1       = {{Chembox Identifiers
| CASNo = 111-65-9
| CASNo_Ref = {{cascite|correct|CAS}}
| UNII_Ref = {{fdacite|correct|FDA}}
| UNII = X1RV0B2FJV
| PubChem = 356
| ChemSpiderID = 349
| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}
| EINECS = 203-892-1
| UNNumber = 1262
| DrugBank = DB02440
| DrugBank_Ref = {{drugbankcite|changed|drugbank}}
| KEGG = C01387
| KEGG_Ref = {{keggcite|correct|kegg}}
| MeSHName = octane
| ChEBI = 17590
| ChEBI_Ref = {{ebicite|changed|EBI}}
| ChEMBL = 134886
| ChEMBL_Ref = {{ebicite|correct|EBI}}
| RTECS = RG8400000
| Beilstein = 1696875
| Gmelin = 82412
| 3DMet = B00281
| SMILES = CCCCCCCC
| StdInChI = 1S/C8H18/c1-3-5-7-8-6-4-2/h3-8H2,1-2H3
| StdInChI_Ref = {{stdinchicite|correct|chemspider}}
| StdInChIKey = TVMXDCGIABBOFY-UHFFFAOYSA-N
| StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}
}}
| Section2       = {{Chembox Properties
| Formula = {{chem2|CH3(CH2)6CH3}}
| C=8|H=18
| Appearance = Colourless liquid
| Odor = Gasoline-like<ref name=PGCH/>
| Density = 0.703 g/cm<sup>3</sup>
| MeltingPtK = 216.0 to 216.6
| BoilingPtK = 398.2 to 399.2
| Solubility = 0.007 mg/dm<sup>3</sup> (at 20&nbsp;°C)
| LogP = 4.783
| VaporPressure = 1.47 kPa (at 20.0&nbsp;°C)
| HenryConstant = 29 nmol/(Pa·kg)
| RefractIndex = 1.398
| Viscosity = {{plainlist|
* 0.509 mPa·s (25&nbsp;°C)<ref name="Dymond1994">{{cite journal|last1=Dymond|first1=J. H.|last2=Oye|first2=H. A.|title=Viscosity of Selected Liquid ''n''-Alkanes|journal=Journal of Physical and Chemical Reference Data|volume=23|issue=1|year=1994|pages=41–53|issn=0047-2689|doi=10.1063/1.555943|bibcode=1994JPCRD..23...41D}}</ref>
* 0.542 mPa·s (20&nbsp;°C)}}
| MagSus = −96.63·10<sup>−6</sup> cm<sup>3</sup>/mol
| ConjugateAcid = [[Octonium]]
}}
| Section3       = {{Chembox Thermochemistry
| DeltaHf = −252.1 to −248.5 kJ/mol
| DeltaHc = −5.53 to −5.33 MJ/mol
| Entropy = 361.20 J/(K·mol)
| HeatCapacity = 255.68 J/(K·mol)
}}
| Section4       = {{Chembox Hazards
| GHSPictograms = {{GHS flame}} {{GHS exclamation mark}} {{GHS health hazard}} {{GHS environment}}
| GHSSignalWord = '''DANGER'''
| NFPA-H = 1
| NFPA-F = 3
| NFPA-R = 0
| HPhrases = {{H-phrases|225|304|315|336|410}}
| PPhrases = {{P-phrases|210|261|273|301+310|331}}
| FlashPtC = 13.0
| AutoignitionPtC = 220.0
| ExploLimits = 0.96 – 6.5%
| IDLH = 1000 ppm<ref name=PGCH>{{PGCH|0470}}</ref>
| REL = TWA 75 ppm (350 mg/m<sup>3</sup>) C 385 ppm (1800 mg/m<sup>3</sup>) [15-minute]<ref name=PGCH/>
| PEL = TWA 500 ppm (2350 mg/m<sup>3</sup>)<ref name=PGCH/>
| LDLo = 428 mg/kg (mouse, intravenous)<ref>{{IDLH|111659|Octane}}</ref>
}}
| Section5       = {{Chembox Related
| OtherFunction_label = alkanes
| OtherFunction = {{Unbulleted list|[[Methane]]|[[Ethane]]|[[Propane]]|[[Butane]]|[[Pentane]]|[[Hexane]]|[[Heptane]]|}}
}}
| Verifiedfields = changed
| Watchedfields  = changed
| verifiedrevid  = 411133144
}}

'''Octane''' is a [[hydrocarbon]] and also an [[alkane]] with the [[chemical formula]] C<sub>8</sub>H<sub>18</sub>, and the condensed structural formula CH<sub>3</sub>(CH<sub>2</sub>)<sub>6</sub>CH<sub>3</sub>. Octane has many [[structural isomer]]s that differ by the location of branching in the [[carbon chain]]. One of these isomers, [[2,2,4-Trimethylpentane|2,2,4-trimethylpentane]] (commonly called iso-octane), is used as one of the standard values in the [[octane rating]] scale.

Octane is a component of [[gasoline]] and petroleum. Under [[standard temperature and pressure]], octane is an odorless, colorless liquid. Like other short-chained alkanes with a low molecular weight, it is [[Volatility (chemistry)|volatile]], flammable, and toxic. Octane is 1.2 to 2 times more toxic than [[heptane]].<ref>{{Cite web |date=2020-02-27 |title=1988 OSHA PEL Project - Octane {{!}} NIOSH {{!}} CDC |url=https://www.cdc.gov/niosh/pel88/111-65.html |access-date=2024-04-19 |website=www.cdc.gov }}</ref>