Physical and chemical properties of Selenium

Atomic Number:34
Element Symbol:Se
Element Name:Selenium
Atomic Weight:78.96
Group Number:16
Group Name:Chalcogen
Period Number:4
Ground State Configuration:[Ar] 3d10 4s2 4p4
Ground State Level:3P2
Standard State:Solid
Common Valences:2,4,6
Bond Length:232.1
Atomic Radius Empirical:115
Atomic Radius Calculated:103
Covalent Radius Empirical:116
Vander Waals Radius:190
Electron Affinity:195.0
First Ionization Energy:941.0
Pauling Electronegativity:2.55
Sanderson Electronegativity:3.01
Allred Rochow Electronegativity:2.48
Mulliken Jaffe Electronegativity:2.60
Allen Electronegativity:2.424
Density Of Solid:4819
Molar Volume:16.42
Velocity Of Sound:3350
Youngs Modulus:10
Rigidity Modulus:3.7
Bulk Modulus:8.3
Poissons Ratio:0.33
Mineral Hardness:2.0
Brinell Hardness:736
Electrical Resistivity:high
Refractive Index:1.000895
Melting Point:221
Boiling Point:685
Critical Temperature:1493
Thermal Conductivity:0.52
Enthalpy Of Fusion:5.4
Enthalpy Of Vaporization:26
Enthalpy Of Atmization:227
Most Common Oxidation Numbers:6,4,2,-2
Color:Grey, metallic lustre
Discovered By:Jons Berzelius
Discovered At:Sweden
Discovered When:1817
Origin Of Name:From the Greek word selene meaning moon

Calculate the molecular weight of Selenium or molecular weight Se.

Also see the full list of chemical elements and atomic weights.

Compounds that contain Selenium