| 释义 |
WordReference Random House Unabridged Dictionary of American English © 2024ru•bid•i•um (ro̅o̅ bid′ē əm),USA pronunciation n. [Chem.]- Chemistrya silver-white, metallic, active element resembling potassium, used in photoelectric cells and radio vacuum tubes. Symbol: Rb;
at. wt.: 85.47;
at. no.: 37;
sp. gr.: 1.53 at 20°C.
- Neo-Latin, equivalent. to Latin rūbid(us) red (in allusion to the two red lines in its spectrum) + -ium -ium
- 1860–65
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