Tellurium (Te)
Tellurium (symbol Te) is the chemical element with atomic number 52: a metalloid, solid at 0 °C, with an atomic mass of 127.6 u. Discovered in 1782 (Franz-Joseph Müller von Reichenstein).
Tellurium is one of the rarest metalloids in Earth's crust, about as rare as gold. Yet it lies at the heart of thin-film solar panels and small compressor-free coolers. The slightest contact with its compounds gives you garlic-smelling breath for weeks.
Key facts
- Atomic number
- 52
- Symbol
- Te
- French name
- Tellure
- Atomic mass
- 127.6 u
- Molar mass
- 127.6 g/mol
- Family
- Metalloids
- Position
- period 5, group 16, p-block
- State at 0 °C
- Solid
- Melting point
- 449.5 °C
- Boiling point
- 987.9 °C
- Density
- 6.24 g/cm³
- Electronegativity (Pauling)
- 2.1
- First ionization energy
- 869 kJ/mol
- Atomic radius
- 140 pm
- Electron configuration
- [Kr] 4d¹⁰ 5s² 5p⁴
- Abundance in Earth's crust
- 0.001 ppm (79th most abundant element)
- Indicative price
- 64 $/kg (order of magnitude)
- Radioactive
- no
- Discovery
- 1782, Franz-Joseph Müller von Reichenstein
Origin of the name
From the Latin tellus, Earth.
What does tellurium look like?
A shiny, brittle, silvery-white solid with a metallic look. Ground into powder, it is gray.
Where is tellurium found?
About 0.001 ppm of Earth's crust, or roughly one gram per thousand tonnes. Curiously, it forms minerals with gold, the tellurides, which played a part in several gold rushes.
Natural sources
- Calaverite
- Sylvanite
- Tellurobismuthite
- Native tellurium
How is tellurium produced?
Like selenium, it is recovered from the anode slimes of electrolytic copper refining. World refined output is about 600 to 700 tonnes a year, mostly in China.
Top producers
- China
- Russia
- Sweden
- Japan
- Canada
What is tellurium used for?
- Cadmium telluride solar panels.
- Thermoelectric modules (bismuth telluride) for cooling or generating electricity.
- Steel and copper alloys that are easier to machine.
- Phase-change layers in rewritable discs.
- Vulcanizing rubber.
In everyday life
- Electric car cooler (Peltier module)
- Thin-film solar farm
- Rewritable DVD or Blu-ray
Role in living things
No known biological role. The body turns absorbed tellurium into dimethyl telluride, a volatile molecule that gives breath and sweat a strong garlic smell.
Hazards of tellurium
Its compounds are toxic at high doses. Even tiny exposures, in the lab or in industry, cause persistent garlic breath, a telltale sign well known to chemists.
Cosmic origin
- Neutron stars: Created when two neutron stars collide — the “forge” of gold.
History of tellurium
In 1782, Franz-Joseph Müller von Reichenstein, a mining inspector in Transylvania, studied a gold ore that did not behave as expected and suspected a new metal in it. In 1798, Martin Heinrich Klaproth confirmed the discovery and named it after tellus, Latin for Earth.
Did you know?
- According to a story often told in Kalgoorlie, Australia, waste rock rich in calaverite, an unrecognized gold telluride, was used to fill in streets before its value was understood in 1896.
- Tellurium and selenium, named after the Earth and the Moon, are neighbors in the periodic table.
- Bismuth telluride Peltier modules cool with no moving parts at all, simply by passing an electric current.
Isotopes of tellurium
Six stable isotopes and two barely radioactive ones. Tellurium-128 holds the record for the longest half-life ever measured: about a hundred trillion times the age of the Universe.
- tellurium-120: 0.09% of natural tellurium, stable
- tellurium-122: 2.55% of natural tellurium, stable
- tellurium-123: 0.89% of natural tellurium, stable
- tellurium-124: 4.74% of natural tellurium, stable
- tellurium-125: 7.07% of natural tellurium, stable
- tellurium-126: 18.84% of natural tellurium, stable
- tellurium-128: 31.74% of natural tellurium, radioactive, half-life 2.2 × 10²⁴ years. The longest half-life ever measured for a nucleus.
- tellurium-130: 34.08% of natural tellurium, radioactive, half-life 7.91 × 10²⁰ years. Studied for double beta decay to uncover the true nature of the neutrino.
- tellurium-132: radioactive, half-life 3.2 days. Fission product released in the Chernobyl and Fukushima accidents.
Related elements
Same family (metalloids): Boron (B), Silicon (Si), Germanium (Ge), Arsenic (As), Antimony (Sb).
Same column (group 16): Oxygen (O), Sulfur (S), Selenium (Se), Polonium (Po), Livermorium (Lv).