Rare Earth Elements

The Rare Earth Elements

58 Cerium(Ce): melting point- 765c boiling point-3360c

EX:Glass polishing powders


59 Praseodymium(Pr): melting point- 935c boiling point- 3290c

EX:Strong magnets


60 Neodymium(Nd): melting point- 1024c boiling point- 3100c

EX:Additive in glasses


61 Promethium(Pm): melting point-1100c boiling point- 3000c

EX:One stable oxidation

Promethium

Earlt discovered promethium in 1924 but these appear have been substantiated. A group at Ohio State University (USA) claimed element 61 in experiments involving its synthesis in a cyclotron, but again the evidence did not satisfy everyone. In 1947, Marinsky, Glendenin, and Coryell at Oak Ridge, Tennessee, USA, made the first chemical identification of promethium





Were these Earth metals can be found

Safety concerns about rare earth elements

1) Our sources of rare earth elements are decreasing and having a higher demand

2) Some of the rare earth elements are very toxic such as lanthanum