Selenium vs Cadmium

PropertySe SeleniumCd Cadmium
Atomic number3448
SymbolSeCd
NameSeleniumCadmium
Categorynonmetaltransition-metal
Standard Atomic Weight78.971 u112.414 u
Period45
Group1612
Blockps
Phase at STPsolidsolid
Electron configuration[Ar]4s23d104p4[Kr]5s24d10
Oxidation states[-2, -1, 0, 1, 2, 3, 4, 5, 6][-2, 1, 2]
Electronegativity (Pauling)2.551.69
Electron affinity2.0206 eV-0.7 eV
Density4809 kg/m³8690 kg/m³
Melting point220.5 °C321.07 °C
Boiling point684.85 °C766.85 °C
Discovery year18171817