单词 | ruthenium |
释义 | Word Frequency ruthenium(ruːˈθiːnɪəm) noun a hard brittle white element of the platinum metal group. It occurs free with other platinum metals in pentlandite and other ores and is used to harden platinum and palladium. Symbol: Ru; atomic no: 44; atomic wt: 101.07; valency: 0–8; relative density: 12.41; melting pt: 2334°C; boiling pt: 4150°C Word origin C19: from Medieval Latin Ruthenia Russia, where it was first discovered |
随便看 |
英语词典包含233703条英英释义在线翻译词条,基本涵盖了全部常用单词的英英翻译及用法,是英语学习的有利工具。