Te

Tellurium

Identification

CAS Number: 13494-80-9

Discovery Year: 1782

Discoverer: Franz Müller von Reichenstein

Discovery Location: Romania

Properties

Atomic Mass: 127.6 →Density: 6.232 g/cm³ →

Crust Abundance: 0.001 mg/kg

Crystal Structure: HEX

Atomic Dimensions

Atomic Radius: 140 pm →

Atomic Radius (Rahm): 242 pm

Covalent Radius: 138 pm →

Van der Waals Radius: 206 pm

Metallic Radius: 137 pm

Atomic Volume: 20.5 cm³/mol

Lattice Constant: 4.45 Å

Thermodynamics

Melting Point: 722.7 K →Boiling Point: 1263 K →Specific Heat: 0.201 J/(g·K) →Thermal Conductivity: 14.3 W/(m·K) →Heat of Fusion: 17.91 kJ/mol →Heat of Vaporization: 49.8 kJ/mol →

Heat of Formation: 196.6 kJ/mol

Electronic Structure

Electron Config: [Kr] 4d10 5s2 5p4

Block: p

Period: 5 →Group: 16 →Electronegativity: 2.1 →Electron Affinity: 1.9708759999999999 eV →

Oxidation States: -2, +4, +6

Abundance & Geochemistry

Crust Abundance: 0.001 mg/kg

Geochemical Class: semi-volatile

Goldschmidt Class: chalcophile

About

Silvery metalloid element of group 16. Eight natural isotopes, nine radioactive isotopes. Used in semiconductors and to a degree in some steels. Chemistry is similar to Sulphur. Discovered in 1782 by Franz Miller.

Isotopes

Te-130 130 34.08%

Te-128 128 31.74%

Te-126 126 18.84%

Te-125 125 7.07%

Te-124 124 4.74%

Te-122 122 2.55%

Te-123 123 0.8900%

Te-120 120 0.0900%