Group 3 of the periodic table is composed of the elements scandium, yttrium, and lanthanum. These elements are all transition metals, meaning they have partially filled d-orbitals. Scandium is the lightest of the three and is used in the production of aluminum alloys. Yttrium is used in the production of phosphors, which are used in television and computer screens. Lanthanum is used in the production of camera lenses and in the production of catalysts.
