ASCII PERIODIC TABLE OF THE ELEMENTS
Ho
Relative atomic mass: 164.93032 ± 0.00002
English: Holmium
French: Holmium
Croatian: Holmij
German: Holmium
Italian: Olmio
Spanish: Holmio
Atomic number: 67
Group numbers: 3
Period: 6
Standard state (20 °C): solid
Discovery: 1879 Per Theodor Cleve (SE)
Holmium was discovered by Per Theodore Cleve (SE) in 1879. The origin of the name comes from the Greek word 'Holmia' meaning 'Stockholm'. It is a fairly soft, malleable, lustrous, silvery metal that reacts slowly with oxygen and water. Holmium dissolves in acids and is able to react violently with air or halogens. Holmium occurs in gadolinite but most often it's produced from monazite sand. It has very few practical applications; however, it has some unusual magnetic properties that offer some hope for future applications.
Electronic configuration: [Xe] 4f11 6s2
Formal oxidation number: +3
Atomic radius: 174.3 pm
Electronegativities: 1.23
Thermal conductivity: 16.2 W/(m K)
Electrical resistivity (20 °C): 87 μΩcm
Melting point: 1474 °C
Boiling point: 2700 °C
Heat of fusion: 17.2 kJ/mol
Heat of vaporization: 303 kJ/mol
Heat of atomization: 302.63 kJ/mol
66Dy <= 67Ho => 68Er
ASCII Periodic Table of the Elements
__________________________________
31 Mar. 2008
Copyright © 1998-2008 by Eni Generalic