Atomic Number of Thulium

Thulium Atomic Number

Atomic Number of Thulium is 69.

Chemical symbol for Thulium is Tm. Number of protons in Thulium is 69. Atomic weight of Thulium is 168.93422 u or g/mol. Melting point of Thulium is 1545 °C and its the boiling point is 1727 °C.

» Boiling Point » Melting Point » Abundant » State at STP » Discovery Year

About Thulium

Thulium is one of the lanthanides discovered by Swedish scientists and named after an old name for Scandinavia, Thule. It is a shiny metal of slivery color, which can be extracted from a number of minerals on our planet. Its properties are similar to the ones of other lanthanides. Thulium is not a toxic element and it has no importance for life. The main uses of this element include some lasers and X-ray machines for a variety of medical purposes.

Properties of Thulium Element

Atomic Number (Z)69
Atomic SymbolTm
Atomic Weight168.93422 u
Density9.321 g/cm3
Melting Point (K)1818 K
Melting Point (℃)1545 °C
Boiling Point (K)2223 K
Boiling Point (℃)1727 °C
Heat Capacity0.16 J/g · K
Abundance0.52 mg/kg
State at STPSolid
Electronegativity (Pauling) χ1.25
Ionization Energy (eV)6.18431
Atomic Radius175pm
Covalent Radiusno datapm
Valence Electrons2
Year of Discovery1879

What is the Boiling Point of Thulium?

Thulium boiling point is 1727 °C. Boiling point of Thulium in Kelvin is 2223 K.

What is the Melting Point of Thulium?

Thulium melting point is 1545 °C. Melting point of Thulium in Kelvin is 1818 K.

How Abundant is Thulium?

Abundant value of Thulium is 0.52 mg/kg.

What is the State of Thulium at Standard Temperature and Pressure (STP)?

State of Thulium is Solid at standard temperature and pressure at 0℃ and one atmosphere pressure.

When was Thulium Discovered?

Thulium was discovered in 1879.