Benzene

Simplest aromatic hydrocarbon (&see; aromatic compound), parent substance of a large class of chemical compounds. It was discovered in 1825 by Michael Faraday. The chemical formula is C₆H₆; August Kekule von Stradonitz in 1865 was the first to propose the correct structure, a six-membered ring of carbon atoms, each with one hydrogen atom bonded to it (&see; bonding).

Although benzene is often represented with alternating single and double bonds between carbon atoms, the electrons in the bonds are shared or delocalized in such a way as to make all carbon-carbon bonds alike. Benzene is a colourless, mobile liquid with a characteristic odour. An excellent solvent, it is also widely used as a starting material for many plastics, dyes, detergents, insecticides, and other industrial chemicals. Benzene is highly toxic, and long exposure may cause leukemia.