C8H18

C8H18

The chemical structure of octane, C8H18.

C8H18, also known as octane, is an organic compound belonging to the alkane family. It is a colorless liquid with a distinct odor and is commonly found in petroleum and gasoline. Octane is a vital component in the automotive industry as it serves as a reference fuel for measuring the octane rating of gasoline.

Chemical Properties

Octane is composed of eight carbon atoms and eighteen hydrogen atoms, giving it the chemical formula C8H18. It has a molecular weight of approximately 114.22 grams per mole. The structure of octane consists of a straight chain of carbon atoms, with each carbon atom bonded to four hydrogen atoms.

Uses

Octane is primarily used as a fuel additive in gasoline to improve its performance and prevent engine knocking. It is also utilized as a solvent in various industries, including the manufacturing of paints, adhesives, and cleaning agents. Additionally, octane is employed in laboratory settings as a standard reference compound for gas chromatography.

Octane Rating

The octane rating is a measure of a fuel's ability to resist knocking or pinging during combustion. It indicates the fuel's performance in internal combustion engines. The octane rating of gasoline is determined by comparing its performance to a mixture of iso-octane (C8H18) and heptane (C7H16). Pure iso-octane is assigned an octane rating of 100, while pure heptane has an octane rating of 0. Gasoline with a higher octane rating is more resistant to knocking and is suitable for high-performance engines.

Safety Considerations

Octane is flammable and should be handled with caution. It has a flash point of approximately -18 degrees Celsius (-0.4 degrees Fahrenheit) and can ignite easily in the presence of an open flame or spark. Proper ventilation and safety measures should be followed when working with octane to prevent accidents and ensure personal safety.

See Also

• Alkane
• Gasoline
• Octane rating
• Iso-octane
• Heptane