C8H6

C8H6 is the chemical formula for several hydrocarbons, the most notable being phenylacetylene (also called ethynylbenzene). The formula corresponds to eight carbon atoms and six hydrogen atoms, giving a molecular weight of about 102.13 g/mol. Its degree of unsaturation is 6, which is consistent with a benzene ring (four degrees) bonded to an additional triple bond (two more degrees).

Phenylacetylene is an aromatic alkyne consisting of a benzene ring attached to an ethynyl group (C≡CH). The structure is often represented as C6H5–C≡CH. As the simplest arylacetylene, it serves as a versatile building block in organic synthesis and is used in a range of transformations, including cross-coupling reactions to form substituted arenes and in the preparation of various dyes, polymers, and pharmaceuticals.

In addition to phenylacetylene, the formula C8H6 can correspond to other less common isomers, but phenylacetylene is the best-known representative. It is typically available commercially for laboratory and industrial use as a colorless, volatile liquid with a sharp odor.

Safety and handling notes: C8H6 compounds are generally flammable and can be irritating to the skin, eyes, and respiratory system. They should be stored in a cool, well-ventilated area away from oxidizers and sources of heat. Many acetylenic compounds can polymerize or react in the presence of light or metals, so inhibitors or stabilizers are often used during storage and handling. Proper personal protective equipment and standard laboratory safety practices are advised.