Seleen
34
Se
Groep
16
Periode
4
Blok
p
Protrone
Elektrone
Neutrone
34
34
45
Algemene Eienskappe
Atoom Nommer
34
Atoommassa
78,96
Massa Nommer
79
Kategorie
Niemetale
Kleur
Grys
Radioaktief
Nee
From the Greek word Selene, moon
Kristalstruktuur
Simple Monoclinic
Geskiendenis
Selenium was first observed in about the year 1300 by the alchemist Arnold of Villanova.
Selenium was discovered in 1817 by Jöns Jacob Berzelius and Johan Gottlieb Gahn who noted the similarity of the new element to the previously-known tellurium.
In 1873, Willoughby Smith found that the electrical resistance of grey selenium was dependent on the ambient light.
Selenium was discovered in 1817 by Jöns Jacob Berzelius and Johan Gottlieb Gahn who noted the similarity of the new element to the previously-known tellurium.
In 1873, Willoughby Smith found that the electrical resistance of grey selenium was dependent on the ambient light.
Elektrone per skil
2, 8, 18, 6
Elektronkonfigurasie
[Ar] 3d10 4s2 4p4
Selenium deficiency in animals can lead to slow growth
Fisiese Eienskappe
Fase
Soliede
Digtheid
4,809 g/cm3
Smeltpunt
494,15 K | 221 °C | 429,8 °F
Kookpunt
958,15 K | 685 °C | 1265 °F
Heat of Fusion
5,4 kJ/mol
Heat of Vaporization
26 kJ/mol
Spesifieke Hitte Kapasiteit
0,321 J/g·K
Oorvloed in die aardkors
5×10-6%
Oorvloed in die heelal
3×10-6%
CAS Nommer
7782-49-2
PubChem CID Nommer
6326970
Atomiese Eienskappe
Atoom radius
120 pm
Kovalente Radius
120 pm
Elektronegatiewiteit
2,55 (Pauling scale)
Ionisasie potensiaal
9,7524 eV
Atoom volume
16,45 cm3/mol
Termiese geleidingsvermoë
0,0204 W/cm·K
Oksidasiestate
-2, 2, 4, 6
Toepassings
Selenium is used in the glass industry to decolorize glass and to make red-colored glasses and enamels.
It is used as a catalyst in many chemical reactions.
It is also used as a photographic toner, and as an additive to stainless steel.
Selenium sulfide is used in anti-dandruff shampoos.
It is used as a catalyst in many chemical reactions.
It is also used as a photographic toner, and as an additive to stainless steel.
Selenium sulfide is used in anti-dandruff shampoos.
Many of selenium's compounds, such as selenates and selenites, are highly toxic
Isotope
Stabiele Isotope
74Se, 76Se, 77Se, 78Se, 80SeOnstabiele Isotope
65Se, 66Se, 67Se, 68Se, 69Se, 70Se, 71Se, 72Se, 73Se, 75Se, 79Se, 81Se, 82Se, 83Se, 84Se, 85Se, 86Se, 87Se, 88Se, 89Se, 90Se, 91Se, 92Se, 93Se, 94Se