Assertion: technetium | /r/HasAspect | stable isotopes
Facets:
Source sentences:
text: Technetium has no stable isotopes – the lightest such element.
text: Technetium is a metallic chemical element which does not appear naturally, because it has no stable isotope.
text: Technetium has no stable isotopes, as all of its isotopes are radioactive.
text: If it had stable isotopes, I would likely have studied it.