ASCII PERIODIC TABLE OF THE ELEMENTS

  Pr

Relative atomic mass: 140.90765 +- 0.00002

English: Praseodymium
French: Praseodyme
Croatian: Praseodimij
German: Praseodym
Italian: Praseodimio
Spanish: Praseodimio

Atomic number: 59
Group numbers: 3
Period: 6
Standard state (20 oC): solid

Discovery: 1885 Carl Freiherr Auer von Welsbach (AT)
Praseodymium was discovered by Carl Freiherr Auer von Welsbach (AT) in 1885. The origin of the name comes from the Greek words prasios didymos meaning green twin. It is a silvery white, moderately soft, malleable, ductile metal that reacts slowly with oxygen but reacts rapidly with water. Metal ignites and burns readily. Praseodymium is obtained from same salts as neodymium. It is used with neodymium to make lenses for glass maker's goggles since it filters out the yellow light present in glass blowing. Alloyed with magnesium praseodymium creates a high-strength metal used in aircraft engines. Misch metal, used in the manufacture of pyrophoric alloys for cigarette lighters, contains about 5% praseodymium metal. (Typically composition of misch metal are Ce:Nd:Pr:La:Other rare earth=50:18:6:22:4). The price of 99.9 % pure praseodymium ingot is 184.50 for 50 g.
Electronic configuration: [Xe] 4f3 6s2
Formal oxidation number: +3
Atomic radius: 182 pm

Electronegativities: 1.13
Thermal conductivity: 12.5 W/(m K)
Electrical resistivity (20 oC): 68 microOhm cm

Melting point: 931 oC
Boiling point: 3520 oC

Heat of fusion: 11.3 kJ/mol
Heat of vaporization: 357 kJ/mol
Heat of atomization: 356.69 kJ/mol

58Ce <= 59Pr => 60Nd


ASCII Periodic Table of the Elements
__________________________________
29 Aug. 2017
Copyright © 1998-2017 by Eni Generalic.