The chemical element with the symbol 'Cl' is chlorine. It is a halogen, located in group 17 of the periodic table. Chlorine is a greenish-yellow gas at room temperature and has a pungent, distinctive smell. It is highly reactive and is used in various applications, including water purification, disinfectants, and the manufacturing of plastics, notably PVC (polyvinyl chloride). Due to its reactive nature, chlorine is never found in its elemental form in nature; instead, it is mostly found in combines with other elements, especially in compounds like sodium chloride, commonly known as table salt.