Biphenyl appears as a clear colorless liquid with a pleasant odor. Flash point 180°F. Insoluble in water. Vapors are heavier than air. Used to manufacture other chemicals and as a fungicide. Biphenyl is a benzenoid aromatic compound that consists of two benzene rings connected by a single covalent bond. Biphenyl occurs naturally in coal tar, crude oil, and natural gas. Formerly used as a fungicide for citrus crops. It has a role as an antimicrobial food preservative and an antifungal agrochemical. It is a member of benzenes, an aromatic fungicide and a member of biphenyls.