Tellur

52
Te
Grupp
16
Period
5
Block
p
Protoner
Electrons
Neutroner
52
52
76
Generella Egenskaper
Atomnummer
52
Atommassa
127,6
Mass Number
128
Kategori
Metalloid
Färg
Silver
Radioaktiv
Nej
From the Latin word tellus, earth
Kristallstruktur
Enkelt trigonal
Historia
Tellurium was discovered in Transylvania in 1782 by Franz-Joseph Müller von Reichenstein in a mineral containing tellurium and gold.

In 1789, another Hungarian scientist, Pál Kitaibel, also discovered the element independently in an ore from Deutsch-Pilsen which had been regarded as argentiferous molybdenite.

In 1798, it was named by Martin Heinrich Klaproth who earlier isolated it from the mineral calaverite.
Elektroner per skal
2, 8, 18, 18, 6
Elektronkonfiguration
[Kr] 4d10 5s2 5p4
Te
In air, tellurium burns with a greenish-blue flames, forming the dioxide
Fysikaliska Egenskaper
Aggregationstillstånd
Fast
Densitet
6,232 g/cm3
Smältpunkt
722,66 K | 449,51 °C | 841,12 °F
Kokpunkt
1261,15 K | 988 °C | 1810,4 °F
Smältvärme
17,5 kJ/mol
Ångbildningsvärme
48 kJ/mol
Specifik värmekapacitet
0,202 J/g·K
Abundance in Earth's crust
9,9×10-8%
Abundance in Universe
9×10-7%
Metallic
Bildkrediter: Images-of-elements
Metallic tellurium
CAS Number
13494-80-9
PubChem CID Number
6327182
Atomära Egenskaper
Atomradie
140 pm
Kovalent radie
138 pm
Elektronegativitet
2,1 (Paulingskalan)
Jonisationspotential
9,0096 eV
Molvolym
20,5 cm3/mol
Värmeledningsförmåga
0,0235 W/cm·K
Oxidationstillstånd
-2, 2, 4, 5, 6
Applications
The primary use of tellurium is in alloys, foremost in steel and copper to improve machinability.

Tellurium is used as a basic ingredient in blasting caps, and is added to cast iron for chill control.

It is used in vulcanizing rubber and in catalysts for petroleum cracking.

Tellurium is used as a coloring agent in ceramics.
Tellurium and tellurium compounds are considered to be mildly toxic
Isotoper
Stabila isotoper
120Te, 122Te, 124Te, 125Te, 126Te
Instabila isotoper
105Te, 106Te, 107Te, 108Te, 109Te, 110Te, 111Te, 112Te, 113Te, 114Te, 115Te, 116Te, 117Te, 118Te, 119Te, 121Te, 123Te, 127Te, 128Te, 129Te, 130Te, 131Te, 132Te, 133Te, 134Te, 135Te, 136Te, 137Te, 138Te, 139Te, 140Te, 141Te, 142Te