Rubidium vs Iridium

PropertyRb RubidiumIr Iridium
Atomic number3777
SymbolRbIr
NameRubidiumIridium
Categoryalkali-metaltransition-metal
Standard Atomic Weight85.4678 u192.217 u
Period56
Group19
Blockss
Phase at STPsolidsolid
Electron configuration[Kr]5s1[Xe]6s24f145d7
Oxidation states[-1, 1][-3, -2, -1, 1, 2, 3, 4, 5, 6, 7, 8, 9]
Electronegativity (Pauling)0.822.2
Electron affinity0.4859 eV1.565 eV
Density1530 kg/m³2.256220e+4 kg/m³
Melting point39.31 °C2445.85 °C
Boiling point687.85 °C4427.85 °C
Discovery year18611803