Trans-1,2-dichloroethene is a chemical compound with the formula C2H2Cl2. It is an isomer of dichloroethene, meaning it has the same molecular formula but a different arrangement of atoms. The "trans" designation indicates that the two chlorine atoms are on opposite sides of the double bond, which affects its physical and chemical properties. This compound is primarily used as an intermediate in the production of other chemicals and as a solvent in various industrial applications. It is important to handle trans-1,2-dichloroethene with care, as it can be harmful if inhaled or ingested, and it may pose environmental risks.