Molybdenum vs Iridium

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PropertyMo MolybdenumIr Iridium
Atomic number4277
SymbolMoIr
NameMolybdenumIridium
Categorytransition-metaltransition-metal
Standard Atomic Weight95.95 u192.217 u
Period56
Group69
Blockss
Phase at STPsolidsolid
Electron configuration[Kr]5s14d5[Xe]6s24f145d7
Oxidation states[-4, -2, -1, 0, 1, 2, 3, 4, 5, 6][-3, -2, -1, 1, 2, 3, 4, 5, 6, 7, 8, 9]
Electronegativity (Pauling)2.162.2
Electron affinity0.744 eV1.565 eV
Density1.020000e+4 kg/m³2.256220e+4 kg/m³
Melting point2622.85 °C2445.85 °C
Boiling point4638.85 °C4427.85 °C
Discovery year17781803