PERIODIC ELEMENT
Tm (Thulium)

 



Atomic number : 69
Atomic mass : 168.93 g.mol-1
Electronegativity according to Pauling : 1.2
Density : 9.3 g.cm-3 at 20 °C
Melting point : 1545 °C
Boiling point : 1947 °C
Vanderwaals radius : unknown
Ionic radius : unknown
Isotopes : 5
Electronic shell : [ Xe ] 4f13 6s2
Energy of first ionisation : 595.3 kJ.mol-1
Energy of second ionisation : 1160.7 kJ.mol-1
Energy of third ionisation : 2284 kJ.mol-1
Standard potential : - 2.28 V
Discovered by : Theodore Cleve 1879
 
Atomic Structure Uses (power for portable x-ray machines)