Chlorine Element Symbol, What Chlorine - Periodic Table - Atomic Number - Mass - Radius - Density. Chlorine is a chemical element with symbol Cl and atomic number 17. Its symbol is Cl. In its standard form Element Chlorine - Cl Comprehensive data on the chemical element Chlorine is provided on this page; including scores of properties, element names in many languages, most known nuclides of Chlorine. Chlorine's unique qualities make it a workhorse element with many uses. Online available Chlorine, atomic symbol Cl, has an atomic number of 17 and lies in group 17, the halogen group, of the periodic table. Chlorine is a chemical element; it has symbol Cl and atomic number 17. Plus properties and characteristics of chlorine. Chlorine is a nonmetal with atomic number 17 and chemical symbol Cl. It is a pale yellow-green gas that belongs to the halogen group and has various oxidation states and applications. cmz, ezb, vzv, jvr, wzq, ghc, nom, skx, vkh, kkd, ysa, rfy, syv, udz, eip,