cover image


Chemical element, symbol Te and atomic number 52 / From Wikipedia, the free encyclopedia

Dear Wikiwand AI, let's keep it short by simply answering these key questions:

Can you list the top facts and stats about Tellurium?

Summarize this article for a 10 year old


Tellurium is a chemical element; it has symbol Te and atomic number 52. It is a brittle, mildly toxic, rare, silver-white metalloid. Tellurium is chemically related to selenium and sulfur, all three of which are chalcogens. It is occasionally found in its native form as elemental crystals. Tellurium is far more common in the Universe as a whole than on Earth. Its extreme rarity in the Earth's crust, comparable to that of platinum, is due partly to its formation of a volatile hydride that caused tellurium to be lost to space as a gas during the hot nebular formation of Earth.[9]

Quick facts: Tellurium, Pronunciation, Appearance, Standar...
Tellurium, 52Te
Pronunciation/tɛˈljʊəriəm/ (te-LURE-ee-əm)
Appearancesilvery lustrous gray (crystalline),
brown-black powder (amorphous)
Standard atomic weight Ar°(Te)
Tellurium in the periodic table


Atomic number (Z)52
Groupgroup 16 (chalcogens)
Periodperiod 5
Block  p-block
Electron configuration[Kr] 4d10 5s2 5p4
Electrons per shell2, 8, 18, 18, 6
Physical properties
Phase at STPsolid
Melting point722.66 K (449.51 °C, 841.12 °F)
Boiling point1261 K (988 °C, 1810 °F)
Density (near r.t.)6.24 g/cm3
when liquid (at m.p.)5.70 g/cm3
Heat of fusion17.49 kJ/mol
Heat of vaporization114.1 kJ/mol
Molar heat capacity25.73 J/(mol·K)
Vapor pressure
P (Pa) 1 10 100 1 k 10 k 100 k
at T (K)   (775) (888) 1042 1266
Atomic properties
Oxidation states−2, −1, 0, +1, +2, +3, +4, +5, +6 (a mildly acidic oxide)
ElectronegativityPauling scale: 2.1
Ionization energies
  • 1st: 869.3 kJ/mol
  • 2nd: 1790 kJ/mol
  • 3rd: 2698 kJ/mol
Atomic radiusempirical: 140 pm
Covalent radius138±4 pm
Van der Waals radius206 pm
Color lines in a spectral range
Spectral lines of tellurium
Other properties
Natural occurrenceprimordial
Crystal structure trigonal[3]
Trigonal crystal structure for tellurium
Thermal expansion18 µm/(m⋅K)[4] (at r.t.)
Thermal conductivity1.973.38 W/(m⋅K)
Magnetic orderingdiamagnetic[5]
Molar magnetic susceptibility−39.5×10−6 cm3/mol (298 K)[6]
Young's modulus43 GPa
Shear modulus16 GPa
Bulk modulus65 GPa
Speed of sound thin rod2610 m/s (at 20 °C)
Mohs hardness2.25
Brinell hardness180–270 MPa
CAS Number13494-80-9
Namingafter Roman Tellus, deity of the Earth
DiscoveryFranz-Joseph Müller von Reichenstein (1782)
First isolationMartin Heinrich Klaproth
Isotopes of tellurium
Main isotopes[7] Decay
abun­dance half-life (t1/2) mode pro­duct
120Te 0.09% stable
121Te synth 16.78 d ε 121Sb
122Te 2.55% stable
123Te 0.89% stable[8]
124Te 4.74% stable
125Te 7.07% stable
126Te 18.8% stable
127Te synth 9.35 h β 127I
128Te 31.7% 2.2×1024 y ββ 128Xe
129Te synth 69.6 min β 129I
130Te 34.1% 8.2×1020 y ββ 130Xe
Symbol_category_class.svg Category: Tellurium
| references

Tellurium-bearing compounds were first discovered in 1782 in a gold mine in Kleinschlatten, Transylvania (now Zlatna, Romania) by Austrian mineralogist Franz-Joseph Müller von Reichenstein, although it was Martin Heinrich Klaproth who named the new element in 1798 after the Latin tellus 'earth'. Gold telluride minerals are the most notable natural gold compounds. However, they are not a commercially significant source of tellurium itself, which is normally extracted as a by-product of copper and lead production.

Commercially, the primary use of tellurium is CdTe solar panels and thermoelectric devices. A more traditional application in copper (tellurium copper) and steel alloys, where tellurium improves machinability, also consumes a considerable portion of tellurium production. Tellurium is considered a technology-critical element.[10]

Tellurium has no biological function, although fungi can use it in place of sulfur and selenium in amino acids such as tellurocysteine and telluromethionine.[11] In humans, tellurium is partly metabolized into dimethyl telluride, (CH3)2Te, a gas with a garlic-like odor exhaled in the breath of victims of tellurium exposure or poisoning.

Oops something went wrong: