Chemical data for Ho - Holmium | PhysLink.com

Holmium

 Holmium 
Ho
Atomic Number: 67
Atomic Weight: 164.93032
Element Type: Rare Earth Metal
Crystal Structure: Hexagonal
Melting Point: 1474.0°C = 2685.2°F = 1747.15 K
Boiling Point: 2700.0°C = 4892.0°F = 2973.15 K
Critical Temp: °C = °F = K
Atomic Radius: 2.47 Å (Å = Angstrom = 10-10 m)
Covalent Radius: 1.58 Å
Electronegativity: 1.23

History

(L. Holmia, for Stockholm). The special absorption bands of holmium were noticed in1878 by the Swiss chemists Delafontaine and Soret, who announced the existence of an"Element X." Cleve, of Sweden, later independently discovered the element whileworking on erbia earth. The element is named after cleve's native city. Holmia, the yellowoxide, was prepared by Homberg in 1911. Holmium occurs in gadolinite, monazite, and inother rare-earth minerals. It is commercially obtained from monazite, occurring in thatmineral to the extent of about 0.05%. It has been isolated by the reduction of itsanhydrous chloride or fluoride with calcium metal.


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