Tellurium

  • tellurium, 52te
    tellurium2.jpg
    tellurium
    pronunciationm/ (lewr-ee-əm)
    appearancesilvery lustrous gray (crystalline),
    brown-black powder (amorphous)
    standard atomic weight ar, std(te)127.60(3)[1]
    tellurium in the periodic table
    hydrogen helium
    lithium beryllium boron carbon nitrogen oxygen fluorine neon
    sodium magnesium aluminium silicon phosphorus sulfur chlorine argon
    potassium calcium scandium titanium vanadium chromium manganese iron cobalt nickel copper zinc gallium germanium arsenic selenium bromine krypton
    rubidium strontium yttrium zirconium niobium molybdenum technetium ruthenium rhodium palladium silver cadmium indium tin antimony tellurium iodine xenon
    caesium barium lanthanum cerium praseodymium neodymium promethium samarium europium gadolinium terbium dysprosium holmium erbium thulium ytterbium lutetium hafnium tantalum tungsten rhenium osmium iridium platinum gold mercury (element) thallium lead bismuth polonium astatine radon
    francium radium actinium thorium protactinium uranium neptunium plutonium americium curium berkelium californium einsteinium fermium mendelevium nobelium lawrencium rutherfordium dubnium seaborgium bohrium hassium meitnerium darmstadtium roentgenium copernicium nihonium flerovium moscovium livermorium tennessine oganesson
    se

    te

    po
    antimonytelluriumiodine
    atomic number (z)52
    groupgroup 16 (chalcogens)
    periodperiod 5
    blockp-block
    element category  metalloid
    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, +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 structurehexagonal
    hexagonal crystal structure for tellurium
    speed of sound thin rod2610 m/s (at 20 °c)
    thermal expansion18 µm/(m·k)[2] (at r.t.)
    thermal conductivity1.97–3.38 w/(m·k)
    magnetic orderingdiamagnetic[3]
    magnetic susceptibility−39.5·10−6 cm3/mol (298 k)[4]
    young's modulus43 gpa
    shear modulus16 gpa
    bulk modulus65 gpa
    mohs hardness2.25
    brinell hardness180–270 mpa
    cas number13494-80-9
    history
    namingafter roman tellus, deity of the earth
    discoveryfranz-joseph müller von reichenstein (1782)
    first isolationmartin heinrich klaproth
    main isotopes of tellurium
    iso­tope abun­dance half-life (t1/2) decay mode pro­duct
    120te 0.09% stable
    121te syn 16.78 d ε 121sb
    122te 2.55% stable
    123te 0.89%[5] stable
    124te 4.74% stable
    125te 7.07% stable
    126te 18.84% stable
    127te syn 9.35 h β 127i
    128te 31.74% 2.2×1024 y ββ 128xe
    129te syn 69.6 min β 129i
    130te 34.08% 7.9×1020 y ββ 130xe
    category category: tellurium
    | references

    tellurium is a chemical element with the 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 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,[6] and partly to tellurium's low affinity for oxygen, which causes it to bind preferentially to other chalcophiles in dense minerals that sink into the core.

    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 word for "earth", tellus. 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 copper (tellurium copper) and steel alloys, where it improves machinability. applications in cdte solar panels and cadmium telluride semiconductors also consume a considerable portion of tellurium production. tellurium is considered a technology-critical element.

    tellurium has no biological function, although fungi can use it in place of sulfur and selenium in amino acids such as tellurocysteine and telluromethionine.[7] 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.

  • characteristics
  • history
  • production
  • compounds
  • applications
  • biological role
  • precautions
  • see also
  • references
  • external links

Tellurium, 52Te
Tellurium2.jpg
Tellurium
Pronunciationm/ (LEWR-ee-əm)
Appearancesilvery lustrous gray (crystalline),
brown-black powder (amorphous)
Standard atomic weight Ar, std(Te)127.60(3)[1]
Tellurium in the periodic table
Hydrogen Helium
Lithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon
Sodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine Argon
Potassium Calcium Scandium Titanium Vanadium Chromium Manganese Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton
Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver Cadmium Indium Tin Antimony Tellurium Iodine Xenon
Caesium Barium Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gold Mercury (element) Thallium Lead Bismuth Polonium Astatine Radon
Francium Radium Actinium Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Nihonium Flerovium Moscovium Livermorium Tennessine Oganesson
Se

Te

Po
antimonytelluriumiodine
Atomic number (Z)52
Groupgroup 16 (chalcogens)
Periodperiod 5
Blockp-block
Element category  Metalloid
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, +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 structurehexagonal
Hexagonal crystal structure for tellurium
Speed of sound thin rod2610 m/s (at 20 °C)
Thermal expansion18 µm/(m·K)[2] (at r.t.)
Thermal conductivity1.97–3.38 W/(m·K)
Magnetic orderingdiamagnetic[3]
Magnetic susceptibility−39.5·10−6 cm3/mol (298 K)[4]
Young's modulus43 GPa
Shear modulus16 GPa
Bulk modulus65 GPa
Mohs hardness2.25
Brinell hardness180–270 MPa
CAS Number13494-80-9
History
Namingafter Roman Tellus, deity of the Earth
DiscoveryFranz-Joseph Müller von Reichenstein (1782)
First isolationMartin Heinrich Klaproth
Main isotopes of tellurium
Iso­tope Abun­dance Half-life (t1/2) Decay mode Pro­duct
120Te 0.09% stable
121Te syn 16.78 d ε 121Sb
122Te 2.55% stable
123Te 0.89%[5] stable
124Te 4.74% stable
125Te 7.07% stable
126Te 18.84% stable
127Te syn 9.35 h β 127I
128Te 31.74% 2.2×1024 y ββ 128Xe
129Te syn 69.6 min β 129I
130Te 34.08% 7.9×1020 y ββ 130Xe
Category Category: Tellurium
| references

Tellurium is a chemical element with the 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 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,[6] and partly to tellurium's low affinity for oxygen, which causes it to bind preferentially to other chalcophiles in dense minerals that sink into the core.

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 word for "earth", tellus. 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 copper (tellurium copper) and steel alloys, where it improves machinability. Applications in CdTe solar panels and cadmium telluride semiconductors also consume a considerable portion of tellurium production. Tellurium is considered a technology-critical element.

Tellurium has no biological function, although fungi can use it in place of sulfur and selenium in amino acids such as tellurocysteine and telluromethionine.[7] 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.