Editing Undecane (section)

{{Chembox 
| Watchedfields = changed
| verifiedrevid = 470619567
| ImageFile = Undecane-2D-Skeletal.svg
| ImageFile_Ref = {{chemboximage|correct|??}}
| ImageSize = 255
| ImageClass = skin-invert
| ImageAlt = Structural formula of undecane
| ImageFile1 = UndecaneFull.png
| ImageFile1_Ref = {{chemboximage|correct|??}}
| ImageSize1 = 255
| ImageClass1 = skin-invert
| ImageAlt1 = Skeletal formula of undecane with all implicit carbons shown, and all explicit hydrogens added
| ImageFile2 = Undecane 3D ball.png
| ImageFile2_Ref = {{chemboximage|correct|??}}
| ImageSize2 = 255
| ImageAlt2 = Ball-and-stick model of the undecane molecule
| PIN = Undecane<ref>{{Cite web|title=undecane - Compound Summary|url=https://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?cid=14257&loc=ec_rcs|work=PubChem Compound|publisher=National Center for Biotechnology Information|access-date=5 January 2012|location=USA|date=16 September 2004|at=Identification and Related Records}}</ref>
|Section1={{Chembox Identifiers
| CASNo = 1120-21-4
| CASNo_Ref = {{cascite|correct|CAS}}
| PubChem = 14257
| ChemSpiderID = 13619 
| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}
| UNII = JV0QT00NUE
| UNII_Ref = {{fdacite|correct|FDA}}
| EINECS = 214-300-6
| UNNumber = 2330
| MeSHName = undecane
| ChEBI = 46342
| ChEBI_Ref = {{ebicite|correct|EBI}}
| ChEMBL = 132474
| ChEMBL_Ref = {{ebicite|correct|EBI}}
| RTECS = YQ1525000
| Beilstein = 1697099
| SMILES = CCCCCCCCCCC
| StdInChI = 1S/C11H24/c1-3-5-7-9-11-10-8-6-4-2/h3-11H2,1-2H3
| StdInChI_Ref = {{stdinchicite|correct|chemspider}}
| StdInChIKey = RSJKGSCJYJTIGS-UHFFFAOYSA-N
| StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}
}}
|Section2={{Chembox Properties
| C=11 | H=24 
| Appearance = Colorless liquid
| Odor = Gasoline-like to Odorless
| Density = 740 g/L
| MeltingPtC = -26
| BoilingPtC = 196
| LogP = 6.312
| VaporPressure = 55 Pa (at 25 °C)<ref name="Yaws">{{cite book |last1=Yaws |first1=Carl L.|title= Chemical Properties Handbook|year= 1999|publisher= McGraw-Hill|location= New York|isbn= 0-07-073401-1|pages= 159–179}}</ref>
| HenryConstant = 5.4 nmol Pa<sup>−1</sup> kg<sup>−1</sup>
| RefractIndex = 1.417
| MagSus = −131.84·10<sup>−6</sup> cm<sup>3</sup>/mol
}}
|Section3={{Chembox Thermochemistry
| DeltaHf = −329.8 – −324.6 kJ mol<sup>−1</sup>
| DeltaHc = −7.4339 – −7.4287 MJ mol<sup>−1</sup>
| Entropy = 458.15 J K<sup>−1</sup> mol<sup>−1</sup>
| HeatCapacity = 345.05 J K<sup>−1</sup> mol<sup>−1</sup>
}}
|Section4={{Chembox Hazards
| GHSPictograms = {{GHS flame}} {{GHS health hazard}}
| GHSSignalWord = '''DANGER'''
| HPhrases = {{H-phrases|304|315|319|331|335}}
| PPhrases = {{P-phrases|261|301+310|305+351+338|311|331}}
| FlashPtC = 60.0
| NFPA-H = 3
| NFPA-F = 2
| NFPA-I = 0
| AutoignitionPtC = 240
| LD50 = > 2000 mg/kg (rat, oral)<br> > 5000 mg/kg (rat, dermal)
| LC50 = > 20 mg/L (rat, 8 hours)
| ExternalSDS = [https://www.fishersci.com/msdsproxy%3FproductName%3DAC140660100%26productDescription%3DN-UNDECANE%252C%2B99%2525%2B10LT%26catNo%3DAC140660100%26vendorId%3DVN00032119%26storeId%3D10652 Fisher Scientific]
}}
|Section5={{Chembox Related
| OtherFunction_label = alkanes
| OtherFunction = {{Unbulleted list|[[Decane]]|[[Dodecane]]}}
}}
}}

'''Undecane''' (also known as '''hendecane''') is a liquid [[alkane]] [[hydrocarbon]] with the [[chemical formula]] CH<sub>3</sub>(CH<sub>2</sub>)<sub>9</sub>CH<sub>3</sub>.  It is used as a mild sex attractant for various types of [[moths]] and [[cockroach]]es, and an alert signal for a variety of [[ants]].<ref>{{cite book | author = Hölldobler B, Wilson EO | date = 1990 | title = The Ants | publisher = Harvard University Press | isbn = 0-674-04075-9 | page = 287 }}</ref> It has 159 [[isomer]]s.<ref>{{Cite journal | doi = 10.6084/M9.FIGSHARE.24309724| date = 2023| last1 = Stoermer| first1 = Martin| title = Undecane Isomers | journal = Figshare}}</ref>

Undecane may also be used as an internal standard in gas chromatography when working with other hydrocarbons. Since the boiling point of undecane (196&nbsp;°C) is well known, it may be used as a comparison for retention times in a gas chromatograph for molecules whose structure has been freshly elucidated. For example, if one is working with a 50&nbsp;m crosslinked methyl silicone capillary column with an oven temperature increasing slowly, beginning around 60&nbsp;°C, an 11-carbon molecule like undecane may be used as an internal standard to be compared with the retention times of other 10-, 11-, or 12- carbon molecules, depending on their structures.