Ozone

CAS Number: 10028-15-6. A triatomic, very reactive form of
oxygen that is a bluish, irritating gas of pungent odor. It is
formed naturally in the atmosphere by a photochemical reaction.
It is a major air pollutant in the lower atmosphere but a
beneficial component of the upper atmosphere. Ozone is used for
oxidizing, bleaching, disinfecting, and deodorizing. Chemical
formula = O3. Molecular weight = 47.998 g/mol.