Rubidium vs Osmium

PropertyRb RubidiumOs Osmium
Atomic number3776
SymbolRbOs
NameRubidiumOsmium
Categoryalkali-metaltransition-metal
Standard Atomic Weight85.4678 u190.23 u
Period56
Group18
Blockss
Phase at STPsolidsolid
Electron configuration[Kr]5s1[Xe]6s24f145d6
Oxidation states[-1, 1][-4, -2, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8]
Electronegativity (Pauling)0.822.2
Electron affinity0.4859 eV1.1 eV
Density1530 kg/m³2.258720e+4 kg/m³
Melting point39.31 °C3032.85 °C
Boiling point687.85 °C5011.85 °C
Discovery year18611803