Selenium

Images

Image

Attribution: W. Oelen

Animated Selenium

History

From the Greek word Selene, moon. Discovered by Berzelius in 1817, who found it associated with tellurium (named for the earth).

Uses

Selenium is used in Xerography for reproducing and copying documents, letters, etc. It is used by the glass industry to decolorize glass and to make ruby-colored glasses and enamels. It is also used as a photographic toner, and as an additive to stainless steel.

Isotopes

Naturally selenium contains six stable isotopes. Fifteen other isotopes have been characterized. The element is a member of the sulfur family and resembles sulfur both in its various forms and in its compounds.

General Info

AtomicNumber
34
Symbol
Se
Name
Selenium

Atomic Info

Appearance
AtomicWeight
78.96(3)
Color
FFA100
ElectronicConfiguration
[Ar] 3d10 4s2 4p4
ElectronegativityInPauling
2.55
AtomicRadiusInPM
116
IonRadiusInPM
198 (-2)
VanDerWaalsRadiusInPM
190
IEinKJmol
941
EAinKJmol
-195
OxidationStates
-2, 2, 4, 6
StandardState
solid
BondingType
metallic
MeltingPoint
494
BoilingPoint
958
Density
4.82
State
Polyatomic nonmetal
DiscoveredYear
1817