Selenium vs Tellurium

PropertySe SeleniumTe Tellurium
Atomic number3452
SymbolSeTe
NameSeleniumTellurium
Categorynonmetalmetalloid
Standard Atomic Weight78.971 u127.6 u
Period45
Group1616
Blockpp
Phase at STPsolidsolid
Electron configuration[Ar]4s23d104p4[Kr]5s24d105p4
Oxidation states[-2, -1, 0, 1, 2, 3, 4, 5, 6][-2, -1, 0, 1, 2, 3, 4, 5, 6]
Electronegativity (Pauling)2.552.1
Electron affinity2.0206 eV1.9708 eV
Density4809 kg/m³6232 kg/m³
Melting point220.5 °C449.51 °C
Boiling point684.85 °C987.85 °C
Discovery year18171782