Selenium vs Ruthenium

← Back to Periodic Table
PropertySe SeleniumRu Ruthenium
Atomic number3444
SymbolSeRu
NameSeleniumRuthenium
Categorynonmetaltransition-metal
Standard Atomic Weight78.971 u101.07 u
Period45
Group168
Blockps
Phase at STPsolidsolid
Electron configuration[Ar]4s23d104p4[Kr]5s14d7
Oxidation states[-2, -1, 0, 1, 2, 3, 4, 5, 6][-4, -2, 1, 2, 3, 4, 5, 6, 7, 8]
Electronegativity (Pauling)2.552.2
Electron affinity2.0206 eV1.05 eV
Density4809 kg/m³1.210000e+4 kg/m³
Melting point220.5 °C2333.85 °C
Boiling point684.85 °C4149.85 °C
Discovery year18171828