Assertion: iodine | /r/HasAspect | only one stable isotope
Facets:
Source sentences:
text: Iodine has only one stable isotope.
text: Iodine has only one stable isotope, iodine—127; it is the only isotope of iodine occurring in nature, although 24 iodine isotopes are known.
text: Iodine has only one stable isotope, I-127.