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Thulium

Thulium is a chemical element; it has symbol Tm and atomic number 69. It is the thirteenth element in the lanthanide series of metals. It is the second-least abundant lanthanide in the Earth's crust, after radioactively unstable promethium. It is an easily workable metal with a bright silvery-gray luster. It is fairly soft and slowly tarnishes in air.…

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167Tm
synth
168Tm
synth
169Tm
100%
170Tm
synth
171Tm
synth
Appearance
silvery gray

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Biological role

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Thulium

Nodes133
Edges132
Triples131
Avg. degree1.99
Density0.015038
Components1

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Thulium

Top relations

related to history · 22
Thulium → Ancient Greek, British, Carl Gustaf Mosander, Charles James, Cleve, Durham, Er2O3, He, Iceland, In, New Hampshire College, Per Teodor Cleve, Scandinavia, Swedish, The, This, Thule, Thulium's, Tm, Tu
related to Occurrence · 14
Thulium → Australia, Brazil, China, Earth, Earth's, Greenland, In, India, Its, Like, Solar System, Tanzania, The, United States
related to Lasers · 9
Thulium → Cr, Ho, Holmium-chromium-thulium, It, Single-element, The, This, Tm, YAG
related to Biological role · 7
Thulium → Despite, Humans, In, Liver, Soluble, The, When
related to Production · 6
Thulium → China, In, Newer, None, The, US
related to X-ray source · 6
Thulium → Despite, Such, These, They, Thulium-170, X-ray
related to Isotopes · 4
Thulium → Known, Most, Natural, The
related to Others · 4
Thulium → Because, The, Tm, Tm-doped
related to Physical properties · 4
Thulium → Mohs, Pure, The, Tm
Ionization energies · 3
Thulium → 1st: 596.7 kJ/mol, 2nd: 1160 kJ/mol, 3rd: 2285 kJ/mol

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Important terminology

oxide per compounds used tm metal element lanthanides isotopes cleve first water yttrium also lasers green rare radiation sources state

Entity relationships Subject–Predicate–Object triples

SubjectPredicateObjectConfidenceSrc
Thulium167Tmsynth1.00infobox
Thulium168Tmsynth1.00infobox
Thulium169Tm100%1.00infobox
Thulium170Tmsynth1.00infobox
Thulium171Tmsynth1.00infobox
ThuliumAppearancesilvery gray1.00infobox
Thuliumat T (K)11171.00infobox
ThuliumAtomic number (Z)691.00infobox
ThuliumAtomic radiusempirical: 176 pm1.00infobox
ThuliumBlockf-block1.00infobox
ThuliumBoiling point2223 K ​(1950 °C, ​3542 °F)1.00infobox
ThuliumBrinell hardness470–900 MPa1.00infobox
ThuliumBulk modulus44.5 GPa1.00infobox
ThuliumCAS Number7440-30-41.00infobox
ThuliumCovalent radius190±10 pm1.00infobox
ThuliumCrystal structure​hexagonal close-packed (hcp) (hP2)1.00infobox
ThuliumDensity (at 20° C)9.320 g/cm31.00infobox
ThuliumDiscoveryPer Teodor Cleve (1879)1.00infobox
ThuliumElectrical resistivitypoly: 676 nΩ⋅m (at r.t.)1.00infobox
ThuliumElectron configuration[Xe] 4f13 6s21.00infobox
ThuliumElectronegativityPauling scale: 1.251.00infobox
ThuliumElectrons per shell2, 8, 18, 31, 8, 21.00infobox
ThuliumFirst isolationWilhelm Klemm and Heinrich Bommer (1936)1.00infobox
ThuliumGroupf-block groups (no number)1.00infobox
ThuliumHeat of fusion16.84 kJ/mol1.00infobox
ThuliumHeat of vaporization191 kJ/mol1.00infobox
ThuliumIonization energies1st: 596.7 kJ/mol1.00infobox
ThuliumIonization energies2nd: 1160 kJ/mol1.00infobox
ThuliumIonization energies3rd: 2285 kJ/mol1.00infobox
ThuliumLattice constantsa = 353.77 pm c = 555.39 pm (at 20 °C)1.00infobox

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