Lanthanum Metal (La)-Powder

Lanthanum is a metal rare earth element, chemical symbol La, atomic number 57, atomic weight of 138.90547, element name from Greek, original meaning "concealed". Silver-gray luster, soft texture, density 6.162g/cm3, melting point 920 °C, boiling point 3464 °C (normal pressure), chemically active, exposure to air quickly lose metallic luster to form a blue oxide film, but it can not protect the metal, and then further oxidize to form white oxide powder. It can act slowly with cold water, soluble in acid, and can react with a variety of non-metals. Lanthanum metal is generally stored in mineral oil or noble gases. The content of lanthanum in the earth's crust is 0.00183%, which is second only to cerium in rare earth elements. Lanthanum has two natural isotopes: lanthanum-139 and radioactive lanthanum-138.