Samarium (Sm)

From Wikipedia, the free encyclopediaSamarium is a chemical element with symbol Sm and atomic number 62. It is a moderately hard silvery metal that readily oxidizes in air. Being a typical member of the lanthanide series, samarium usually assumes the oxidation state +3.

Samarium in the periodic table

SymbolSm
Atomic number62
Group0
Period6
Blockf
Element categoryLanthanide

Physical properties

Phase at STPSolid
Density7.52 g/cm3
Atomic weight150.362 u
Melting point1345 K
1071.85 °C
1961.33 °F
Boiling point2173 K
1899.85 °C
3451.73 °F

Atomära egenskaper

Electronegativity (Pauling Scale)1.17
Electron affinity15.63 kJ/mol
Ionization energies
1544.5 kJ/mol
2 1070 kJ/mol
3 2260 kJ/mol
4 3990 kJ/mol

Electron configuration

Electron configuration1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 4f6 5s2 5p6 6s2
Electrons per shell2, 8, 18, 24, 8, 2

History

Discovered1879
Discovered byLecoq de Boisbaudran