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Thorium |
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Symbol: Th
Atomic Number: 90
Mass: 232.0381
Melting Point: 1750.0 C
Boiling Point: 4790.0 C
Number of Protons/Electrons: 90
Number of Neutrons: 142
Classification: Rare Earth
Crystal Structure: Cubic
Density @ 293 K: 11.72 g/cm3
Color: silvery
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Number of Energy Levels: 7
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Isotope | Half Life |
Th-226 | 30.6 minutes |
Th-227 | 18.72 days |
Th-228 | 1.91 years |
Th-229 | 7340.0 years |
Th-230 | 75400.0 years |
Th-231 | 1.06 days |
Th-232 | 1.4E10 years |
Th-233 | 22.3 minutes |
Th-234 | 24.1 days |
Date of Discovery: 1828
Discoverer: Jons Berzelius
Name Origin: Thor (Scandinavian god)
Uses: strong alloys, ultraviolet photoelectric cells
Obtained From: monazite, thorite
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From the Woods Hole Oceanographic Institution