General | States | Energies | Oxidation & Electrons |Appearance & Characteristics
Reactions | Other Forms |Radius | Conductivity | Abundance
Encyclopedia Britannica articles


Name Samarium Symbol Sm
atomic number 62 Atomic weight 150.4
Density @ 293 K 7.54 g/cm3 Atomic volume 19.95 cm3/mol
Group Rare Earth, Lanthanides discovered 1880


state (s, l, g) s
melting point 1345.2 K boiling point 2073 K
Heat of fusion 8.630 kJ/mol Heat of vaporization 166.40 kJ/mol
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1st ionization energy 543.3 kJ/mole electronegativity 1.17
2nd ionization energy 1068 kJ/mole electron affinity 50 kJ/mole
3rd ionization energy 2260 kJ/mole Specific heat 0.20 J/gK
heat atomization 207 kJ/mole atoms

Oxidation & Electrons

Shells 2,8,18,24,8,2 electron configuration [Xe] 4f6 6s2
minimum oxidation number 0 maximum oxidation number 3
min. common oxidation no. 0 max. common oxidation no. 3
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Appearance & Characteristics

structure cp: cls pkd (ABCBCACAB) color silvery-white
uses alloys, headphones toxicity
hardness mohs characteristics


reaction with air vigorous, = Sm2O3 reaction with 6M HCl mild, = H2, SmCl3
reaction with 6M HCl mild, = H2, SmCl3 reaction with 15M HNO3 mild, = Sm(NO3)3
reaction with 6M NaOH
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Other Forms

number of isotopes 7 hydride(s) SmH2 SmH3
oxide(s) Sm2O3 chloride(s) SmCl2 SmCl3


ionic radius (2- ion) pm ionic radius (1- ion) pm
atomic radius 180 pm ionic radius (1+ ion) pm
ionic radius (2+ ion) pm ionic radius (3+ ion) 109.8 pm
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thermal conductivity 13.3 J/m-sec-deg electrical conductivity 11 1/mohm-cm
polarizability 28.8 A^3


source Monazite(phosphate),bastnaesite rel. abund. solar system -0.588 log
abundance earth's crust 0.8 log cost, pure 130 $/100g
cost, bulk $/100g
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World Wide Web presentation of Chemicool Periodic Table is © Copyright 1996-99 by David D. Hsu. Some data were provided by and used with the permission of JCE Software and is owned and copyright by the Division of Chemical Education, Inc. Additional data were provided by Perkin-Elmer through Peter Lykos of IIT. The information may not be redistributed without the permission of David Hsu or JCE Software.