Assertion: astatine | /r/IsA | halogen
Facets:
value: in the periodic table of elements
type: OTHER
value: to be classified as a nonmetal
type: PURPOSE
Source sentences:
text: As a halogen, astatine tends to be classified as a nonmetal.
text: Astatine is a semimetallic chemical element classified among the halogens in the periodic table of elements.