Stable under ordinary conditions. Highly hygroscopic.
GENERAL DESCRIPTION & APPLICATIONS
Lanthanum is a malleable, ductile, soft, silvery white metallic element belonging to group number 3 of periodic table; atomic number 57; atomic mass 138.91; melting point 920°C; boiling point 3464°C; specific gravity 6.162 g/cm3; Oxidation state 3; electronic configuration[Xe] 5d1 6s2.It oxidizes rapidly when exposed to moisture air.Lanthanum is the second most abundant rare-earth element next to cerium. Lanthanide (or lanthanoid) series are the group of rare-earth elements from lanthanum (atomic numbers 57) to 71; their chemical properties are similar to each other. The chemical properties of scandium and yttrium are also similar to the lanthanides; these group are often referred to "rare earth elements".
Lanthanum belongs to the group of transition metal whose atom has an incomplete d sub-shell, or which can give rise to cations with an incomplete d sub-shell; includes elements 21 through 29 (scandium through copper), 39 through 47 (yttrium through silver), 57 through 79 (lanthanumthrough gold), and all elements from 89 (actinium). Minerals which incorporates lanthanum includelanthanite, cordylite,parisite, bastnaesite, synchysite, and monazite. Lanthanum is a major component of misch metal, a pyrophoric alloy used in lighter flints. Small amounts of lanthanum added to steel or iron to improves ductility and to produce nodular cast iron. Rare-earth compounds containing lanthanum are used in carbon lighting applications. Lanthanum is used to replace lime in calcium lights and in optical glass for the alkali resistance, the high refractive index and low dispersion applications. Lanthanum-rich lanthanide compounds are used in cracking reactions as a FCC catalyst. Lanthanum nitrate is a hygroscopic white crystals; melting point 40 C. It is soluble in water and alcohol. It is used as an antiseptic and a catalyst. It is used in gas mantles, specialty glass and water treatment. Lanthanum oxide, also called lanthana; lanthanumsesquioxide; lanthanum trioxide, is a white powder melting point 2000 C. It is insoluble in water but soluble in acids. Lanthanum Oxide is used in manufacturing high transparency and refraction index glass. The end application is precision optics like microscope and telescope lenses and camera components. It is used in preparing special glasses. Lanthanum sulfate is a white crystals. It is slightly soluble in water, soluble in alcohol. It is used for atomic weight determinations for lanthanum.Lanthanum carbonate is a hygroscopic powder soluble in water and acids. It is a component of the catalyst used in cracking reactions. In medicinal use, lanthanum carbonate is used in the treatment of hyperphosphataemia in patients with end stage renal disease.