Thorium (Th) — Actinide. Atomic number 90.
Silvery metal
- Atomic number: 90
- Symbol: Th
- Atomic mass: 232.04 u
- Category: Actinide
- State: Solid
- Melting point: 1749.85 °C / 2023 K
- Boiling point: 4787.85 °C / 5061 K
- Density: 11.72 g/cm³ (20°C)
- Electron configuration: [Rn] 6d2 7s2
- Oxidation states: +4
- Electronegativity: 1.3
- Discovered by: Jöns Jacob Berzelius (1828)
Common uses: Nuclear fuel research, High-temperature ceramics
Biological role: No biological role.
Frequently Asked Questions about Thorium
What is the atomic number of thorium?
Thorium has an atomic number of 90, meaning each atom contains 90 protons in its nucleus.
What is the atomic mass of thorium?
The standard atomic weight of thorium is 232.04 u (unified atomic mass units).
What category does thorium belong to?
Thorium is classified as a actinide.
What is the state of thorium at room temperature?
Thorium is a solid at 20 °C (68 °F).
What is the melting point of thorium?
The melting point of thorium is 1749.85 °C / 2023 K.
What is the boiling point of thorium?
The boiling point of thorium is 4787.85 °C / 5061 K.
What is the density of thorium?
The density of thorium is 11.72 g/cm³ (20°C).
What is the electronegativity of thorium?
Thorium has a Pauling electronegativity of 1.3.
What is the electron configuration of thorium?
The electron configuration of thorium is [Rn] 6d2 7s2.
What are the common oxidation states of thorium?
Thorium commonly exhibits the following oxidation states: +4.
When was thorium discovered?
Thorium was discovered in 1828 by Jöns Jacob Berzelius.
Is thorium radioactive?
Thorium is a naturally occurring radioactive element; all of its isotopes are radioactive.
What is the biological role of thorium?
No biological role.
What are the common uses of thorium?
Thorium is used for: Nuclear fuel research; High-temperature ceramics.
