59
Pr
Praseodymium
140.90766
Atomic Number: 59
Atomic Weight: 140.90766
Melting Point: 1204 K (931°C or 1708°F)
Boiling Point: 3793 K (3520°C or 6368°F)
Density: 6.77 grams per cubic centimeter
Phase at Room Temperature: Solid
Element Classification: Metal
Period Number: 6 Group Number: none Group Name: Lanthanide
What's in a name? From the Greek words prasios and didymos, which together mean "green twin."
Say what? Praseodymium is pronounced as pra-see-oh-DIM-ee-em.
History and Uses:
Praseodymium was discovered by Carl F. Auer von Welsbach, an Austrian chemist, in 1885. He separated praseodymium, as well as the element neodymium, from a material known as didymium. Today, praseodymium is primarily obtained through an ion exchange process from monazite sand ((Ce, La, Th, Nd, Y)PO4), a material rich in rare earth elements.
Praseodymium's primary use is as an alloying agent with magnesium to create high-strength metals that are used in aircraft engines. Praseodymium also makes up about 5% of Misch metal, a material that is used to make flints for lighters. Praseodymium forms the core of carbon arc lights which are used in the motion picture industry for studio lighting and projector lights. Praseodymium is added to fiber optic cables as a doping agent where it is used as a signal amplifier. Praseodymium salts are used to give glasses and enamels a yellow color. Praseodymium is also a component of didymium glass, which is used to make certain types of welder's and glass blower's goggles.
Estimated Crustal Abundance: 9.2 milligrams per kilogram
Estimated Oceanic Abundance: 6.4×10-7 milligrams per liter
Number of Stable Isotopes: 1
Ionization Energy: 5.464 eV
Oxidation States: +3
Electron Shell Configuration:
1s2
2s2 2p6
3s2 3p6 3d10
4s2 4p6 4d10 4f3
5s2 5p6
6s2