Chlorine Chlorine was used as a weapon in World War I. Cl - Chlorine A green, highly reactive gas, chlorine is the most abundant halogen, comprising nearly two percent of the seas and used in all of our laboratory classes. Murium was never found, but Humphrey Davy recognized it's elemental quality in 1810. The oxide is a strong acid.
Crystal are orthorhombic.
Click mass number for decay process, product for element page. Ar-46 46.987976 MASS abund. This is not a publication of Phoenix College.