Chlorinated hydrocarbons are a very large and diverse group of organic molecules. Hydrocarbons are molecules composed entirely of hydrogen (H) and carbon (C) atoms, often derived from carbon-based fossil fuels like petroleum oils and coal. Chlorinated hydrocarbons are specific hydrocarbon molecules that also have atoms of the element chlorine (Cl) chemically bonded to them. The number of chlorine atoms bonded to a specific chlorinated hydrocarbon determines, in part, the properties of the molecule. The number of carbon atoms and how they are arranged in three-dimensions also determines the chemical and physical properties of chlorinated hydrocarbons. Because there is such an immense number of possible forms of chlorinated hydrocarbons, this class of useful compounds has a wide set of applications that are of great economic and practical importance.