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Information valid for Te-128 unless otherwise noted

Basic Information

Symbol: Te
Atomic Number: 52
Mass: 127.6
Melting Point: 449.5 C
Boiling Point: 989.8 C
Number of Protons/Electrons: 52
Number of Neutrons: 76
Classification: Metalloid
Crystal Structure: Hexagonal
Density @ 293 K: 6.24 g/cm3
Color: silverish

Atomic Structure

[Bohr Model of Tellurium]
Number of Energy Levels: 5

  1. First Energy Level: 2
    Second Energy Level: 8
    Third Energy Level: 18
    Fourth Energy Level: 18
    Fifth Energy Level: 6


Isotope Half Life
Te-119 4.69 days
Te-120 Stable
Te-121 16.8 days
Te-121m 154.0 days
Te-122 Stable
Te-123 1.3E12 years
Te-123m 119.7 days
Te-124 Stable
Te-125 Stable
Te-125m 58.0 days
Te-126 Stable
Te-127 9.4 hours
Te-127m 109.0 days
Te-128 Stable
Te-129 1.16 hours
Te-129m 33.6 days
Te-130 2.5E21 years
Te-131 25.0 minutes
Te-131m 1.35 days
Te-132 3.26 days
Te-133 12.4 minutes
Te-133m 55.4 minutes
Te-134 41.8 minutes


Date of Discovery: 1728
Discoverer: Franz Muller von Reichenstein
Name Origin: From the Greek word tellus (Earth)
Uses: coloring of glass and ceramics, thermoelectric devices
Obtained From: by-product of refining of lead and copper