Chemicool

Tm

69

168.9342
Thulium
General | States | Energies | Oxidation & Electrons |Appearance & Characteristics
Reactions | Other Forms |Radius | Conductivity | Abundance
Encyclopedia Britannica articles

General
Name Thulium Symbol Tm
atomic number 69 Atomic weight 168.9342
Density @ 293 K 9.33 g/cm3 Atomic volume 18.1 cm3/mol
Group Rare Earth, Lanthanides discovered 1879

States
state (s, l, g) s
melting point 1818.2 K boiling point 2000 K
Heat of fusion 16.840 kJ/mol Heat of vaporization 191.0 kJ/mol
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Energies
1st ionization energy 596.7 kJ/mole electronegativity 1.25
2nd ionization energy 1163 kJ/mole electron affinity 50 kJ/mole
3rd ionization energy 2544 kJ/mole Specific heat 0.16 J/gK
heat atomization 232 kJ/mole atoms

Oxidation & Electrons
Shells 2,8,18,31,8,2 electron configuration [Xe] 4f13 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 hcp: hexagonal close pkd color silvery-white
uses alloys toxicity
hardness mohs characteristics soft

Reactions
reaction with air vigorous, = Tm2O3 reaction with 6M HCl mild, = H2, TmCl3
reaction with 6M HCl mild, = H2, TmCl3 reaction with 15M HNO3 mild, = Tm(NO3)3
reaction with 6M NaOH
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Other Forms
number of isotopes 1 hydride(s) TmH2 TmH3
oxide(s) Tm2O3 chloride(s) TmCl2 TmCl3

Radius
ionic radius (2- ion) pm ionic radius (1- ion) pm
atomic radius 176 pm ionic radius (1+ ion) pm
ionic radius (2+ ion) 117 pm ionic radius (3+ ion) 102 pm
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Conductivity
thermal conductivity 16.9 J/m-sec-deg electrical conductivity 13.5 1/mohm-cm
polarizability 21.8 A^3

Abundance
source Monazite(phosphate),bastnaesite rel. abund. solar system -1.423 log
abundance earth's crust -0.3 log cost, pure 4100 $/100g
cost, bulk $/100g
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