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67Ho164.930
Holmium
LanthanideHolmium is a chemical element with symbol Ho and atomic number 67. Part of the lanthanide series, holmium is a rare earth element. Holmium was discovered by Swedish chemist Per Theodor Cleve.
Phase: SolidAppearance: silvery white
2, 8, 18, 29, 8, 2
Physical Properties
Atomic Mass164.930332 u
Density8.79 g/cm³
Melting Point1734 K
Boiling Point2873 K
Molar Heat27.15 J/(mol·K)
Period6
PhaseSolid
Chemical Properties
Electron Configuration1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f11
Semantic Config[Xe] 4f11 6s2
Shells2, 8, 18, 29, 8, 2
Electron Affinity32.61 kJ/mol
Electronegativity1.23
Ionization Energies
IE1: 581 kJ/molIE2: 1140 kJ/molIE3: 2204 kJ/molIE4: 4100 kJ/mol
Discovery
Discovered byMarc Delafontaine