Isocetane

Last updated
Isocetane
Isocetane.png
Names
IUPAC name
2,2,4,4,6,8,8-Heptamethylnonane [1]
Identifiers
3D model (JSmol)
ChEBI
ChemSpider
ECHA InfoCard 100.022.280 OOjs UI icon edit-ltr-progressive.svg
EC Number
  • 224-506-8
MeSH 2,2,4,4,6,8,8-heptamethylnonane
PubChem CID
UNII
  • InChI=1S/C16H34/c1-13(10-14(2,3)4)11-16(8,9)12-15(5,6)7/h13H,10-12H2,1-9H3 Yes check.svgY
    Key: VCLJODPNBNEBKW-UHFFFAOYSA-N Yes check.svgY
  • C(C)(C)CC(C)CC(C)(C)CC(C)(C)C
Properties
C16H34
Molar mass 226.448 g·mol−1
AppearanceColourless liquid
Odor Odourless
Density 793 mg mL−1
Boiling point 240.1 °C; 464.1 °F; 513.2 K
Vapor pressure 130 Pa (at 20 °C)
1.439
Thermochemistry
458.80 J K−1 mol−1
Hazards
Flash point 96.00 °C (204.80 °F; 369.15 K)
Related compounds
Related alkanes
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Isocetane (2,2,4,4,6,8,8-heptamethylnonane) is a highly branched alkane used as a reference in determining the cetane number of diesel. It has a cetane number of 15. [2] Isocetane replaced 1-methylnaphthalene in 1962 as the lower reference for cetane number (1-methylnaphthalene has cetane number zero) owing to the oxidation instability and difficulty of use of 1-methylnaphthalene in the reference engine. [3] [4]

Strictly speaking, if the standard meaning of ‘iso’ is followed, the name isocetane should be reserved for the isomer 2-methylpentadecane. However, 2,2,4,4,6,8,8-heptamethylnonane is by far the most important isomer of cetane and so, historically, it has ended up with this name.

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<span class="mw-page-title-main">Cahn–Ingold–Prelog priority rules</span> Naming convention for stereoisomers of molecules

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<span class="mw-page-title-main">Coordination complex</span> Molecule or ion containing ligands datively bonded to a central metallic atom

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<span class="mw-page-title-main">Stereoisomerism</span> When molecules have the same atoms and bond structure but differ in 3D orientation

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Naphthalene is an organic compound with formula C
10
H
8
. It is the simplest polycyclic aromatic hydrocarbon, and is a white crystalline solid with a characteristic odor that is detectable at concentrations as low as 0.08 ppm by mass. As an aromatic hydrocarbon, naphthalene's structure consists of a fused pair of benzene rings. It is the main ingredient of traditional mothballs.

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Hexadecane (also called cetane) is an alkane hydrocarbon with the chemical formula C16H34. Hexadecane consists of a chain of 16 carbon atoms, with three hydrogen atoms bonded to the two end carbon atoms, and two hydrogens bonded to each of the 14 other carbon atoms.

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A chemical substance is a unique form of matter with constant chemical composition and characteristic properties. Chemical substances may take the form of a single element or chemical compounds. If two or more chemical substances can be combined without reacting, they may form a chemical mixture. If a mixture is separated to isolate one chemical substance to a desired degree, the resulting substance is said to be chemically pure.

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References

  1. "2,2,4,4,6,8,8-heptamethylnonane - Compound Summary". PubChem Compound. USA: National Center for Biotechnology Information. 26 March 2005. Identification and Related Records. Archived from the original on 30 October 2013. Retrieved 12 March 2012.
  2. Speight, James G. (2015). Handbook of Petroleum Product Analysis. Hoboken, NJ: Wiley. pp. 158–159. ISBN   978-1-322-95015-0. OCLC   903318141.
  3. "Cetane number". Archived from the original on 2014-03-12. Retrieved 2007-03-01.
  4. Jääskeläinen, Hannu (2007). Fuel Property Testing: Ignition Quality. DieselNet Technology Guide (Technical report). ECOpoint Inc. Archived from the original on 2019-06-26. Retrieved 2021-02-24.