Naphthalene. Computer model of a molecule of the aromatic hydrocarbon naphthalene. This organic chemical is best known for its use in mothballs, though as it is toxic and thought to cause cancer, it is now replaced in modern mothballs with the chlorinated aromatic para-dichlorobenzene (PDB, see A700/302). Naphthalene is also used as an intermediate material in the chemical industry. Other names include tar camphor and albocarbon. It is a volatile solid that forms a vapour (sublimes) at room temperature. The molecule consists of two fused benzene rings. The molecule's chemical formula is C10.H8. The atoms are colour-coded spheres in this ball-and-stick model: carbon (light grey) and hydrogen (dark grey).