The periodic Table
coloured by Discovery
coloured by States
Constants, Astronomy
Constants, Physics
SI Units
by Peder Axensten

Se


in WebElements
in X-Ray info 		Se, 34
selenium (English)
sélénium, m. (French)
Selen, n. (German)
selen (Russian)
selen (Swedish)

Symbol, numberSe, 34 (non-metal), Group: 16; 6A
Weight78.96
In Nature
Discovered1817, by J.J. Berzelius (Sweden)
Density  [kg/m3]4790 [293 K] (solid)   3987 [490 K] (liquid)   
Molar volume16.48 cm3
Melting Temperature490 K   (217 °C)   Enthalpy: 26.32 kJ/mol
Boiling Temperature958.1 K   (685.1 °C)   Enthalpy: 5.1 kJ/mol
Electrical resistance0.01 [293 K] Wm
ThermalConductivity: 2.04 [300 K] W/Km     Expansion: 36.9E-6 /K
Configuration1s2 2s2p6 3s2p6d10 4s2p4
Ionisation [kJ/mol]
  M-->  M+--> M2+--> M3+--> M4+--> M5+--> M6+--> M7+--> M8+--> M9+-->M10+
Thermodynamics
State DfH° DfG° S° CpH H°298.15-H°0
[kJ/mol] [J/Kmol] [kJ/mol]
Isotopes
Mass In nature Half-life Spin m/mN NMM Decay
Se