n-Heptane is the straight-chain alkane with the chemical formula H3C(CH2)5CH3 or C7H16. When used as a test fuel component in anti-knock test engines, a 100% heptane fuel is the zero point of the octane rating scale (the 100 point is a 100% iso-octane). Octane number equates to the anti-knock qualities of a comparison mixture of heptane and isooctane which is expressed as the percentage of isooctane in heptane and is listed on pumps for gasoline dispensed in the United States and internationally.

Substance name:heptane
Trade name:Heptane
EC no:927-510-4
CAS no:64742-49-0
HS code:27101225
Synonyms:alkane C7 / ASTM normal-heptane knock test reference fuel / dipropylmethane / dipropylmethane (=normal-heptane) / ESSO heptane / gettysolve-C / heptane, anhydrous / Heptanes / heptyl hydride / hexylmethane / HYDROSOL-HEPTANE / methylhexane / ndipropylmethane / n-heptane / n-heptyl hydride / normal-dipropylmethane / normal-heptane / normal-heptyl hydride / NORPAR 7 / protein sequencer reagent S1 / SBP 94/99 / skellysolve C / solvent heptane)