octane: Definition and Much More from Answers.com

For the gasoline rating system, see Octane rating, or for other uses, see Octane (disambiguation).

Thermodynamic data

Identifiers
CAS number	111-65-9
RTECS number	RG8400000
SMILES	CCCCCCCC
Properties
Molecular formula	C₈H₁₈
Molar mass	114.2285 g/mol
Appearance	colorless liquid
Density	0.703 g/ml, liquid
Melting point	−57 °C (216 K)
Boiling point	125.52 °C (398.7 K)
Solubility in water	Immiscible
Viscosity	0.542 cP at 20 °C
Thermochemistry
Std enthalpy of formation Δ_fH^o₂₉₈	−250 kJ/mol
Std enthalpy of combustion Δ_cH^o₂₉₈	−5430 kJ/mol
Hazards
EU classification	Flammable (F) Harmful (Xn) Dangerous for the environment (N)
R-phrases	R11, R38, R50/53, R65, R67
S-phrases	(S2), S9, S16, S29, S33, S60, S61, S62
Flash point	13 °C
Autoignition temperature	220 °C
Related Compounds
Related alkanes	Heptane 2,2,4-Trimethylpentane
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox disclaimer and references

Octane is an alkane with the chemical formula CH₃(CH₂)₆CH₃. It has 18 isomers.

One of the isomers, 2,2,4-trimethylpentane or isooctane, is of major importance, as it has been selected as the 100 point on the octane rating scale, with n-heptane as the zero point. Octane ratings are ratings used to represent the anti-knock performance of petroleum-based fuels (octane is less likely to prematurely combust under pressure than heptane), given as the percentage of 2,2,4-trimethylpentane in an 2,2,4-trimethylpentane / n-heptane mixture that would have the same performance. It is an important constituent of gasoline.

Octane has 18 isomers:

Octane (n-octane)
2-Methylheptane
3-Methylheptane
4-Methylheptane
3-Ethylhexane
2,2-Dimethylhexane
2,3-Dimethylhexane
2,4-Dimethylhexane
2,5-Dimethylhexane
3,3-Dimethylhexane
3,4-Dimethylhexane
2-Methyl-3-ethylpentane
3-Methyl-3-ethylpentane
2,2,3-Trimethylpentane
2,2,4-Trimethylpentane (isooctane)
2,3,3-Trimethylpentane
2,3,4-Trimethylpentane
2,2,3,3-Tetramethylbutane

References

External links

Alkanes
Methane CH₄	\|		Ethane C₂H₆	\|		Propane C₃H₈	\|		Butane C₄H₁₀	\|		Pentane C₅H₁₂	\|		Hexane C₆H₁₄
Heptane C₇H₁₆	\|		Octane C₈H₁₈	\|		Nonane C₉H₂₀	\|		Decane C₁₀H₂₂	\|		Undecane C₁₁H₂₄	\|		Dodecane C₁₂H₂₆

This entry is from Wikipedia, the leading user-contributed encyclopedia. It may not have been reviewed by professional editors (see full disclaimer)

Donate to Wikimedia

octane	Easton Octane Skates
octane elliptical	red octane ignition pad

		Dictionary. The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2007. Published by Houghton Mifflin Company. All rights reserved. Read more
		WordNet. WordNet 1.7.1 Copyright © 2001 by Princeton University. All rights reserved. Read more
		Wikipedia. This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Octane". Read more
		Translations. Copyright © 2007, WizCom Technologies Ltd. All rights reserved. Read more

octane

References

External links

Tackle These

Keep Reading