Книга: Praseodymium: Chemical Element, Atomic Number, Abundance of the Chemical Elements, List of Chemical Element Name Etymologies, List of Elements by Atomic Number, Lanthanoid

High Quality Content by WIKIPEDIA articles! Praseodymium is a chemical element that has the symbol Pr and atomic number 59. Praseodymium is a soft, silvery, malleable and ductile metal in the lanthanoid group. It is somewhat more resistant to corrosion in air than europium, lanthanum, cerium, or neodymium, but it does develop a green oxide coating that spalls off when exposed to air, exposing more metal to oxidation ? a centimeter-sized sample of Pr completely oxidizes within a year. For this reason, praseodymium is usually stored under a light mineral oil or sealed in glass.