Assertion: thorium | /r/PartOf | the actinide series
Facets:
value: in the periodic table
type: LOCATION
Source sentences:
text: Although thorium belongs to the actinide series, some of its properties are similar to those of elements in the second subgroup of Group IV of Mendeleev’s periodic system, namely Ti, Zr, and Hf.
text: Thorium belongs to actinide series in the periodic table.
text: Thorium is a radioactive chemical element that belongs to the actinide series.