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69 - Thulium lanthanide

Discovered by Per Teodor Cleve in 1879

Thulium

Thulium is a chemical element with symbol Tm and atomic number 69. It is the thirteenth and antepenultimate (third-last) element in the lanthanide series. Like the other lanthanides, the most common oxidation state is +3, seen in its oxide, halides and other compounds.
Shell Electrons Orbitals
1 2 2 in 1s
2 8 2 in 2s + 6 in 2p
3 18 2 in 3s + 6 in 3p + 10 in 3d
4 31 2 in 4s + 6 in 4p + 10 in 4d + 13 in 4f
5 8 2 in 5s + 6 in 5p
6 2 2 in 6s
ThuliumTm Electron 1 Electron 2 Electron 1 Electron 2 Electron 3 Electron 4 Electron 5 Electron 6 Electron 7 Electron 8 Electron 1 Electron 2 Electron 3 Electron 4 Electron 5 Electron 6 Electron 7 Electron 8 Electron 9 Electron 10 Electron 11 Electron 12 Electron 13 Electron 14 Electron 15 Electron 16 Electron 17 Electron 18 Electron 1 Electron 2 Electron 3 Electron 4 Electron 5 Electron 6 Electron 7 Electron 8 Electron 9 Electron 10 Electron 11 Electron 12 Electron 13 Electron 14 Electron 15 Electron 16 Electron 17 Electron 18 Electron 19 Electron 20 Electron 21 Electron 22 Electron 23 Electron 24 Electron 25 Electron 26 Electron 27 Electron 28 Electron 29 Electron 30 Electron 31 Electron 1 Electron 2 Electron 3 Electron 4 Electron 5 Electron 6 Electron 7 Electron 8 Electron 1 Electron 2
168.93  u Atomic Mass
2.4  Å Atomic Radius
2223  K Boiling Point
1.9  Å Covalent Radius
9.32  g/cm³ Density
99 Electron Affinity
1.25 Electronegativity
6.18  eV First Ionization Energy
1818.15  K Melting Point
6 Number of Shells
69 Atomic Number
2, 8, 18, 31, 8, 2 Electron Shell Occupations