C₂H₃Cl, synonyms: Ethylene, chloro-; Chloroethene; Chloroethylene; Monochloroethylene; Vinyl chloride; Vinyl chloride monomer. This colorless gas is used mainly to produce polyvinylchloride. As there are no natural sources known for this compound, all sources are anthropogenic. The compound reacts with hydroxyl radicals in the troposphere to yield chlorine radicals.