Assertion: astatine's isotope | /r/HasAspect | short half lives
Facets:
Source sentences:
text: All the isotopes of astatine are radioactive and has very short half lives; consequently is a dangerous element.
text: Since its isotopes have such short half-lives there are no commercially significant compounds of astatine.
text: Is has been little researched because all its isotopes have short half lives.