n-Heptane is the straight-chain alkane. 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 (petrol) dispensed globally
1. HEPTANE S is widely applied in laboratories as a non-polar solvent. As a liquid, it is ideal for transport and storage. In the grease spot test, HEPTANE S is used to dissolve an oil spot to show the previous presence of organic compounds on a stained paper. This is done by shaking the stained paper in a HEPTANE S solution for about half a minute.
2. Aqueous bromine may be distinguished from aqueous iodine by its appearance after extraction into HEPTANE S . In water, both bromine and iodine appear brown. However, iodine turns purple when dissolved in HEPTANE S , whereas the bromine solution remains brown.
3. HEPTANE S is commercially available as mixed isomers for use in paints and coatings, as the rubber cement solvent "Bestine", the outdoor stove fuel "Powerfuel" by Primus, as pure n-HEPTANE S for research and development and pharmaceutical manufacturing and as a minor component of gasoline.