Selenium

Symbol SeAtomic number 34
Atomic mass
78.96
Thermal conductivity
0.0204
Atomic radius
1.22
Covalent radius
1.16
Density
4.80
Atomic volume
16.45
Melting point
490
Oxidation states
-2,4,6
Boiling point
958
Stable isotopes
5
Heat of vapor.
37.7
Electronegativity
2.55
Heat of fusion
6.694
First ionization
9.752
Specific heat
0.32
Electrical conduct.
...
Electron configuration

General descriptionNuclear data
Index

Periodic Table

Chemistry concepts
 
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Selenium

Selenium occurs as a gray material and as a red allotropic material. The gray material has a small electrical conductivity in the dark which increases dramatically with exposure to light. This property is used in "selenium cells" for light sensors for control applications.

Selenium is used to impart a ruby-red color to glass and to neutralize the green color in glass which is present due to iron content.

Selenium is similar to sulfur in its chemical properties. One mineral form of selenium is the compound with lead, clausthalite, PbSe.

Atomic dataNuclear data
Index

Periodic Table

Chemistry concepts

Reference
Pauling
Ch. 16
 
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Selenium Nuclear Data

Z
A
Atomic
Mass (u)
Nuclear
Mass(GeV/c2
Binding
Energy(MeV)
Spin
Natural
Abund.
Half-life
Decay
Q
MeV
34
74
73.922475
68.8415
642.90
0
0.009
stable
...
...
34
76
75.919212
70.7015
662.08
0
0.09
stable
...
...
34
77
76.919913
71.6336
669.50
1/2
0.076
stable
...
...
34
78
77.917308
72.5627
680.00
0
0.236
stable
...
...
34
79
78.918498
73.4953
686.96
7/2
...
60ky
b-
0.15
34
80
79.916520
74.4250
696.88
0
0.499
stable
...
...
34
82
81.916698
76.2882
712.85
0
0.089
1.4E20y
double b-
2.99
Atomic data
Index

Periodic Table

Chemistry concepts

Reference
Rohlf
 
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