Praseodymium is a chemical element with the symbol Pr and atomic number 59. It is the third member of the lanthanide series and is traditionally considered to be one of the rare-earth metals. Praseodymium is a soft, silvery, malleable and ductile metal, valued for its magnetic, electrical, chemical, and optical properties.
Phase at STP： solid
Melting point： 1208 K (935 °C, 1715 °F)
Boiling point： 3403 K (3130 °C, 5666 °F)
Density (near r.t.)： 6.77 g/cm3
when liquid (at m.p.)： 6.50 g/cm3
Heat of fusion： 6.89 kJ/mol
Heat of vaporization： 331 kJ/mol
Molar heat capacity： 27.20 J/(mol·K)
As the lanthanides are so similar, praseodymium can substitute for most other lanthanides without significant loss of function, and indeed many applications such as mischmetal and ferrocerium alloys involve variable mixes of several lanthanides, including small quantities of praseodymium. Due to its role in permanent magnets used for wind turbines, it has been argued that praseodymium will be one of the main objects of geopolitical competition in a world running on renewable energy. But this perspective has been criticised for failing to recognise that most wind turbines do not use permanent magnets and for underestimating the power of economic incentives for expanded production.