ELEMENTLE

Element 52 · Metalloid

Tellurium

Period 5 · Group 16

Tellurium is a chemical element with symbol Te and atomic number 52. It is a brittle, mildly toxic, rare, silver-white metalloid. Tellurium is chemically related to selenium and sulfur.

Three reasons Tellurium stands out

  1. 1

    Used in alloys and solar cells.

  2. 2

    Ingesting even a tiny amount causes an intense garlic-like odour on the breath that can persist for weeks.

  3. 3

    Despite being a solid metalloid, it is actually rarer in the Earth's crust than gold.

A solar material named for the Earth

Tellurium is rarer in Earth’s crust than many precious metals, yet it concentrates as a by-product of copper refining. Cadmium telluride converts sunlight into electricity in thin-film panels. The element’s name comes from tellus, Latin for Earth, while its chemical relatives include sulfur and selenium.

Tellurium at a glance
Atomic number / protons52
SymbolTe
Family (Elementle)Metalloid
Classification (PubChem)Metalloid
Period5
Group16
Atomic mass (u)127.6
Standard stateSolid
Electron configuration[Kr]5s2 4d10 5p4
Reported oxidation states+6, +4, -2
Electronegativity (Pauling)2.1
Atomic radius (pm)206
First ionization energy (eV)9.010
Electron affinity (eV)1.971
Density (g/cm³)6.232
Melting point722.66 K (449.51 °C)
Boiling point1261 K (987.85 °C)
Discovery (PubChem)1782

Values are reference data, not a specification for every temperature, pressure, or allotrope. Unknown properties are left unavailable. Superheavy-element predictions remain uncertain.

Sources & further reading

PubChem: Tellurium · Tellurium on Wikipedia

The introduction and original editorial story are adapted from Wikipedia contributors via Periodic-Table-JSON. Element descriptions and their adaptations are available under CC BY-SA 3.0. Numerical attributes use the PubChem periodic-table dataset, retrieved September 22, 2026.