Assertion: pm | /r/HasProperty | chemical element
Facets:
value: with atomic number
type: OTHER
value: with the symbol
type: OTHER
Source sentences:
text: Promethium is a chemical element with the symbol Pm and atomic number 61.
text: Promethium, originally prometheum, is a chemical element with the symbol Pm and atomic number 61.
text: Promethium is a chemical element with the symbol Pm and atomic number 61.
text: Promethium (Pm), chemical element, the only rare-earth metal of the lanthanide series of the periodic table not found in nature on Earth.