The Thrifty Element Tellurium


Introduction to Tellurium

The element tellurium is a brittle, lustrous metalloid. Solar panels and both CDs and DVDs contain tellurium element. 

10 Fun Facts About Tellurium

  • Tellurium is one of the rarest elements on Earth, but plentiful in space. 
  • The rarity of the tellurium element is present in the earth’s crust at about 0.001 parts per million.
  • Tellurium comes from the Latin word tellus, which means earth.
  • The element is a semiconductor that shows a greater electrical conductivity in certain directions or when exposed to light.
  • Tellurium is often used to improve the machinability of copper and stainless steel.
  • Most organisms can metabolize tellurium to make dimethyl telluride, which is a garlic-smelling chemical.
  • If someone eats a tellurium compound, it gives them garlic breath.
  • Tellurium is highly toxic, and may be fatal if inhaled, swallowed or absorbed through skin.
  • Tellurium has no known biological role.
  • Tellurium is most abundant in China.

Tellurium in the Periodic Table

Tellurium has the atomic symbol Te with an atomic number of 52, in the p-block of the periodic table, with antimony to its left and iodine to its right. It is one of the six metalloids on the periodic table. Tellurium has an electron configuration of [Kr] 4d105s25p4. Additionally, the element has an electronegativity of 2.1 on the Pauling scale.

Tellurium’s Application in Today’s World

Tellurium in the Everyday House

Despite its rarity, tellurium can still be found around your own house. For starters, you can look around and find some ceramics bought for decoration made from tellurium. Rewritable CDs and DVDs are also products from the element tellurium. Additionally, tellurium is heavily used in making solar panels, making it an important resource as we transition toward renewable energy. When looking out your window, you may also find that it is tinted glass and this is because there is tellurium present in it.

tinted glass contains tellurium element

Tellurium in the Future

Nevertheless, many expect that tellurium demand will rise gradually over the next 15 to 20 years, particularly as the world’s carbon footprint decreases and solar energy technology spreads.

Where is Tellurium Found?

Tellurium is present in the Earth’s crust only in about 0.001 parts per million, mostly in ionic compounds. It also exists in its elemental form in nature, but only very rarely.

When and How was the Tellurium Element Discovered?

Franz Joseph Müller von Reichenstein, a miner from Romania, made the discovery of tellurium in 1782. In Transylvania, Reichenstein served as the main inspector of all mines, smelters, and saltworks. He also had interest in chemistry and discovered a new metal called aurum album from a gold ore that he thought was antimony. He soon recognized that the metal he had created was really a previously unknown element and not antimony at all. Before 1798, when German scientist Martin Heinrich Klaproth noted the substance in a report, most did not know Reichenstein’s discovery. Although Klaproth gave the new element the name tellurium, Reichenstein eventually received full credit for his discovery. 

Tellurium Element Chemistry – Compounds, Reactions, Isotopes, Oxidation States

Tellurium Compounds and Reactions

  • Tellurides: H2Te
    • H2 + Te → H2Te
      • (This is a synthesis reaction where one mole of Dihydrogen (H2) and one mole of Tellurium (Te) combine to form one mole of Hydrogen Telluride (H2Te).
  • Oxides: TeO2
  • Nitrides: [Te6N8(TeCl2)4(THF)4]
  • Halides: TeF6, TeI, TeBr4, [TeCl4]4, TeF4, TeI4, TeCl2
    • Te + 3F2 → TeF6
      • (This is a synthesis reaction where one mole of Tellurium (Te) and three moles of difluoride (F2) combine to form Tellurium hexafluoride (TeF6).
    • Te + I → TeI
      • (This is a synthesis reaction where one mole of Tellurium (Te) and one mole of Iodine (I) combine to form Tellurium monoiodide (TeI).
    • Te + 2Br2 → TeBr4
      • (This is a synthesis reaction where one mole of Tellurium (Te) and two moles of dibromine (Br2) combine to form one mole of Tellurium tetrabromide (TeBr4).
    • Te + Cl2 → TeCl2
      • (This is a synthesis reaction where one mole of Tellurium (Te) and one mole of dichloride (Cl2) combine to form Tellurium dichloride (TeCl2).
  • Organotelluriums:
    • Li2Te + 2RBr → R2Te + 2 LiBr
      • (This is a double displacement reaction where reduced organotellurium compounds commonly arise from NaHTe and lithium telluride).
    • Te + ArLi → ArTeLi
      • (This is a synthesis reaction where a direct route to organolithium compounds starts from reactions of organolithium or Grignard reagents and Te).
    • Organotelluride anions can be oxidized or alkylated:
      • 2 RTeLi + 0.5 O2 + H2O → RTeTeR + 2LiOH
      • RTeLi + R’Br → RTeR’ + LiBr
  • Salts: TeO3, TeO4

Isolation of Elemental Tellurium

Elemental tellurium readily separates from water as a solid phase. Using a cone with an aqueous LiCl medium, a strongly basic anion-exchanger separates tellurium from many metals. Tellurium has been separated as bromide by distillation from cone, phosphoric acid at about 300°C.

Tellurium Isotopes

The eight naturally occurring isotopes of tellurium include the mass numbers 120 (0.10% nominal natural abundances), 122 (2.60%), 123 (0.91%), 124 (4.82%), 125 (7.14%), 126 (19.0%), 128 (31.7%), and 130 (33.8%).

Tellurium Oxidation States

Tellurium exhibits a large number of oxidation states such as −2, 0, +4, and +6.

Properties of Tellurium Element

  • Atomic Symbol: Te
  • Melting point: 449.5°C 
  • Boiling point: 988°C 
  • Density: 6.24 g/ml 
  • Atomic weight: 127.6 
  • Atomic number: 52
  • Electronegativity: 2.1 
  • Molar heat capacity: 25.7 J/(mol*K) 
  • Classification: metalloid
  • Natural abundance in the Earth’s crust: 0.001 ppm
  • Electron shell configuration: [Kr] 4d105s25p4
  • Stable Isotopes: Tellurium 120, Tellurium 122, Tellurium 123, Tellurium 124, Tellurium 125, Tellurium 126, Tellurium 128, Tellurium 130 
  • Found naturally in the minerals: Aluminum, copper, lead, and tin
  • Toxicity: Exposure to Tellurium can cause headache, fatigue, dizziness, drowsiness and weakness.

Where Can I Buy Tellurium Element?

Pure tellurium costs around $100 per kilogram. You can buy them from online sellers such as those on amazon.