出典:Wiktionary
出典:『Wiktionary』 (2026/03/20 01:55 UTC 版)
rhenium (countable and uncountable, plural rheniums)
| Chemical element | |
|---|---|
| Re | |
| Previous: wolframium (W) | |
| Next: osmium (Os) | |
出典:Wikipedia
出典:『Wikipedia』 (2011/07/18 20:42 UTC 版)
Rhenium (pronunciation: /ˈriːniəm/ ree-nee-əm) is a chemical element with the symbol Re and atomic number 75. It is a silvery-white, heavy, third-row transition metal in group 7 of the periodic table. With an average concentration of 1 part per billion (ppb), rhenium is one of the rarest elements in the Earth's crust. The free element has the third-highest melting point of any element, exceeded only by tungsten and carbon. Rhenium resembles manganese chemically and is obtained as a by-product of molybdenum and copper refinement. Rhenium shows in its compounds a wide variety of oxidation states ranging from −1 to +7.