90Th
Element 90
Thorium
Actinides
Thorium is a chemical element with symbol Th and atomic number 90.
Key data
- Atomic number
- 90
- Atomic mass
- 232.038 u
- Group / Period
- 3 / 7
- Block
- f-block
- Phase at STP
- Solid
- Density
- 11.724 g/cm³
- Melting point
- 1749.8 °C
- Boiling point
- 4787.9 °C
- Electron configuration
- [Rn] 6d2 7s2
Common uses
- •Camp lantern mantles
- •Nuclear fuel research
- •High-quality lenses
Discovery
Year: 1828
Discovered by: Jöns Jakob Berzelius
Frequently asked questions
What is the atomic number of Thorium?
Thorium has atomic number 90. Its symbol is Th and its atomic mass is 232.038 u.
What category of element is Thorium?
Thorium is classified as actinides. It sits in group 3, period 7 of the periodic table.
What is Thorium used for?
Common uses of Thorium include: Camp lantern mantles, Nuclear fuel research, High-quality lenses.
When was Thorium discovered?
Thorium was discovered in 1828 by Jöns Jakob Berzelius.
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