Molybdenum vs Promethium

PropertyMo MolybdenumPm Promethium
Atomic number4261
SymbolMoPm
NameMolybdenumPromethium
Categorytransition-metallanthanide
Standard Atomic Weight95.95 u145 u
Period56
Group6N/A
Blockss
Phase at STPsolidsolid
Electron configuration[Kr]5s14d5[Xe]6s24f5
Oxidation states[-4, -2, -1, 0, 1, 2, 3, 4, 5, 6][2, 3]
Electronegativity (Pauling)2.16N/A
Electron affinity0.744 eV0.129 eV
Density1.020000e+4 kg/m³7260 kg/m³
Melting point2622.85 °C1041.85 °C
Boiling point4638.85 °C2999.85 °C
Discovery year17781902