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 General | States | Energies | Oxidation & Electrons | Appearance & Characteristics | Reactions | Other Forms Radius | Conductivity | Abundance


Name: Tellurium Symbol: Te
Group: Non-Metal, Chalcogen Atomic weight: 127.60
Density @ 293 K: 6.24 g/cm3 Atomic volume: 20.5 cm3/mol
Group: Non-Metal, Chalcogen discovered: 1783


state (s, l, g): s
melting point: 722.7 K boiling point: 1263 K
Heat of fusion: 17.490 kJ/mol Heat of vaporization: 52.550 kJ/mol


1st ionization energy: 869.2 kJ/mole
electronegativity: 2.1 2nd ionization energy: 1794.6 kJ/mole
electron affinity: 190.16 kJ/mole 3rd ionization energy: 2697.7 kJ/mole
Specific heat: 0.20 J/gK heat atomization: 197 kJ/mole atoms

Oxidation & Electrons:

Shells: 2,8,18,18,6 electron configuration: [Kr] 4d10 5s2 5p4
minimum oxidation number: -2 maximum oxidation number: 6
min. common oxidation no.: 0 max. common oxidation no.: 6

Appearance & Characteristics:

structure: parallel chains color: silvery
uses: semiconductors, steel toxicity: yes
hardness: 2.3 mohs characteristics: semimetal


reaction with air: mild, w/ht, =>TeO2
reaction with 6M HCl: none reaction with 6M HCl: none
reaction with 15M HNO3: mild, =>Te(IV) reaction with 6M NaOH:

Other Forms:

number of isotopes: 8 hydride(s): H2Te
oxide(s): TeO2 TeO3 chloride(s): Te2Cl Te3Cl2 Te4Cl16


ionic radius (2- ion): 207 pm ionic radius (1- ion): pm
atomic radius: 142 pm ionic radius (1+ ion): pm
ionic radius (2+ ion): pm ionic radius (3+ ion): pm


thermal conductivity: 11.54 J/m-sec-deg
electrical conductivity: 0 1/mohm-cm polarizability: 5.5 A^3


source: Zn/Pb smelting by-product
rel. abund. solar system: 0.682 log abundance earth's crust: -3 log
cost, pure: 24 $/100g cost, bulk: $/100g