Gasoline is a complex mixture of over 500 hydrocarbons that may have between 5 to 12 carbons. Alkanes type compounds, either straight chain or branched coupounds are present is greatest amounts. Smaller amounts of alkane cyclic and aromatic compounds are present. Very small or trace amounts of alkenes are present in gasoline. A few examples are given here. Self Quiz on gasoline compounds.

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Compound	Octane number	Static Graphic Image	CHIME Interactive Image*
Paraffins or Alkanes
n-butane	113	Graphic	Chime
n-pentane	62	Graphic	Chime
n-hexane	19	Graphic	Chime
n-heptane	0	Graphic	Chime
2-methylbutane	99	Graphic	Chime
2,2-dimethylpropane	100	Graphic	Chime
2,2-dimethylbutane	89	Graphic	Chime
2,2-dimethylpentane	89	Graphic	Chime
2,2,3-trimethylbutane	113	Graphic	Chime
2,2,4-trimethylpentane (isooctane)	100	Graphic	Chime
Olefins or Alkenes
1-pentene	152	Graphic	Chime
2-methyl-2-butene	176	Graphic	Chime
3-methyl-2-pentene	130	Graphic	Chime
2,4,4-trimethyl-1-pentene	164	Graphic	Chime
Cycloalkanes or Naphthenes
cyclopentane	141	Graphic	Chime
methylcyclopentane	107	Graphic	Chime
cyclohexane	110	Graphic	Chime
1,2-dimethylcyclohexane	104	Graphic	Chime
1,4-dimethylcyclohexane	66	Graphic	Chime
Aromatics
Benzene	99	Graphic	Chime
Toluene or methylbenzene	124	Graphic	Chime
m-xylene or 1,3-dimethylbenzene	145	Graphic	Chime
Ethylbenzene	124	Graphic	Chime
Propylbenzene	127	Graphic	Chime
Isopropylbenzene	132	Graphic	Chime