出典:Wiktionary
出典:『Wiktionary』 (2025/04/18 21:32 UTC 版)
thoron (uncountable)
While the chemical symbol "Tn" was at some point assigned to the isotope thoron, said isotope of radon is perhaps better called by the symbol Rn, to make it clear that it is an isotope of radon with said mass number.