noun🔗Share氡 The chemical element (symbol Rn, formerly Ro) with atomic number 86. It is an odorless, colorless, chemically inert but radioactive noble gas."Many homes are tested for radon because this invisible, radioactive gas can be harmful to breathe. "许多房屋都会检测氡气，因为这种无色无味、具有放射性的气体如果被人吸入，可能会对健康造成危害。elementchemistrysubstancescienceChat with AIVocabulary GamePractice Reading
