Praseodymium

59
Pr
140.90765

praseodymium.gif (7166 bytes)
Praseodymium is used cryogenic refrigeration.

Properties

Symbol Name Atomic Number Atomic Weight Group Number
Pr Praseodymium 59 140.90765

Description

Standard State: Solid at 298 K
Color: silvery white, yellowish tinge

In 1841, Mosander extracted the rare earth didymia from lanthana; in 1879, Lecoq de Boisbaudran isolated a new earth, samaria, from didymia obtained from the mineral samarskite. Six years later in 1885, von Welsbach separated didymia into two other earths, praseodymium and meodymia, which gave salts of different colors. Praseodymium can be prepared by several methods, such as by calcium reduction of the anhydrous chloride of fluoride. Misch metal, used in making cigarette lighters, contains about 5% praseodymium metal.