Periodic Table of Elements

Element Thulium - Tm

Comprehensive data on the chemical element Thulium is provided on this page; including scores of properties, element names in many languages, most known nuclides of Thulium. Common chemical compounds are also provided for many elements. In addition technical terms are linked to their definitions and the menu contains links to related articles that are a great aid in one's studies.

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Overview of Thulium

Thulium's Name in Other Languages

  • Latin: Thulium
  • Czech: Thulium
  • Croatian: Tulij
  • French: Thulium
  • German: Thulium - s
  • Italian: Tulio
  • Norwegian: Thulium
  • Portuguese: Túlio
  • Russian: Тулий
  • Spanish: Túlio
  • Swedish: Tulium

Atomic Structure of Thulium

Chemical Properties of Thulium

Physical Properties of Thulium

  • Atomic Mass Average: 168.9342
  • Boiling Point: 2220K 1947°C 3537°F
  • Coefficient of lineal thermal expansion/K-1: 13.3E-6
  • Conductivity
    Electrical: 0.015 106/cm Ω
    Thermal: 0.168 W/cmK
  • Density: 9.32g/cc @ 300K
  • Description:
    Silver colored rare earth metal that tarnishes in air and reacts with water. It is the rarest of the rare earth metals.
  • Elastic Modulus:
    • Bulk: 44.5/GPa
    • Rigidity: 30.5/GPa
    • Youngs: 74/GPa
  • Enthalpy of Atomization: 247 kJ/mole @ 25°C
  • Enthalpy of Fusion: 16.8 kJ/mole
  • Enthalpy of Vaporization: 191 kJ/mole
  • Flammablity Class:
  • Freezing Point: see melting point
  • Hardness Scale
    • Brinell: 471 MN m-2
    • Vickers: 520 MN m-2
  • Heat of Vaporization: 191kJ/mol
  • Melting Point: 1818K 1545°C 2813°F
  • Molar Volume: 18.12 cm3/mole
  • Physical State (at 20°C & 1atm): Solid
  • Specific Heat: 0.16J/gK
  • Vapor Pressure = 0.0049Pa@1545°C

Regulatory / Health

  • CAS Number
    • 7440-30-4
  • OSHA Permissible Exposure Limit (PEL)
    • No limits set by OSHA
  • OSHA PEL Vacated 1989
    • No limits set by OSHA
  • NIOSH Recommended Exposure Limit (REL)
    • No limits set by NIOSH
  • Levels In Humans:
    Note: this data represents naturally occuring levels of elements in the typical human, it DOES NOT represent recommended daily allowances.
    • Blood/mg dm-3: n/a
    • Bone/p.p.m: n/a
    • Liver/p.p.m: n/a
    • Muscle/p.p.m: n/a
    • Daily Dietary Intake: n/a
    • Total Mass In Avg. 70kg human: n/a
  • Discovery Year: 1879
  • Name Origin:
    From Thule, the ancient name of Scandinavia.
  • Abundance of Thulium:
    • Earth's Crust/p.p.m.: 0.48
    • Seawater/p.p.m.:
      • Atlantic Suface: 1.3E-07
      • Atlantic Deep: 1.6E-07
      • Pacific Surface: 7E-08
      • Pacific Deep: 3.3E-07
    • Atmosphere/p.p.m.: N/A
    • Sun (Relative to H=1E12): 1.8
  • Sources of Thulium:
    the chief ores are monazite and bastnasite. Annual world production is around 50 tons. Primary mining areas are USA, Brazil, India, Sri Lanka and Australia.
  • Uses of Thulium:
    Radioactive thulium is used to power portable x-ray machines, eliminating the need for electrical equipment.
  • Additional Notes:

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A list of reference sources used to compile the data provided on our periodic table of elements can be found on the main periodic table page.

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