Assertion: xenon | /r/IsA | noble gas
Facets:
Source sentences:
text: Xenon was discovered in 1898 and is classified as a noble gas.
text: Xenon is a chemical element categorised as a noble gas – a group of six chemical elements which are generally clear, odourless and very stable under the typical atmospheric temperatures and pressures we consider acceptable here on earth.
text: Xenon is a chemical element classified among the noble gases.