Thorium is a natural chemical element.
Thorium is a natural chemical element, a radioactive metal.
Thorium is a natural, radioactive, chemical element; chemically, thorium is homogeneous.
Thorium has 90 electrons.
Thorium is a chemical element not so reactive.
Thorium is a natural chemical element.
The chemical symbol of thorium is Th.
Thorium is a member of actinoids family.
Thorium is a tetravalent element (4+).
Thorium (Th).
Thallium Wrong, check the periodic table, it's "Thorium" number 90 on the table
The chemical symbol for thorium is Th.
Thorium is an inner transition element, which means it is a metal.