90Th

Thorium

Actinide

Properties of Thorium

Atomic number (Z)
90
Symbol
Th
Name
Thorium
Atomic mass
232.038 u
Period
7
Group
Family
Actinides (f-block)
Classification
Actinide
Electron configuration
[Rn] 6d² 7s²

About Thorium

Thorium is a chemical element with symbol Th and atomic number 90 (atomic mass of about 232.038 u). It is classified as a actinide on the periodic table.

On the periodic table, Thorium is located in period 7, outside the numbered groups (f-block), belonging to the actinides (f-block) family. An element's position reveals trends in its properties, such as atomic radius, electronegativity and metallic character.

The electron configuration of Thorium is [Rn] 6d² 7s², which determines how it forms chemical bonds and takes part in reactions.

External references