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Rhenium is a chemical element; it has symbol Re and atomic number 75. It is a silvery-gray, heavy, third-row transition metal in group 7 of the periodic table . With an estimated average concentration of 1 part per billion (ppb), rhenium is one of the rarest elements in the Earth's crust .
Rhenium(VI) oxide has an appearance similar to that of copper. Rhenium(IV) oxide (or rhenium dioxide) is an oxide of rhenium, with the formula ReO 2. This gray to black crystalline solid is a laboratory reagent that can be used as a catalyst. It adopts the rutile structure. It forms via comproportionation: [4] 2 Re 2 O 7 + 3 Re → 7 ReO 2
Refractory metals have high melting points, with tungsten and rhenium the highest of all elements, and the other's melting points only exceeded by osmium and iridium, and the sublimation of carbon. These high melting points define most of their applications. All the metals are body-centered cubic except rhenium which is hexagonal close-packed.
Rhenium trioxide or rhenium(VI) oxide is an inorganic compound with the formula ReO 3. It is a red solid with a metallic lustre that resembles copper in appearance. It is the only stable trioxide of the Group 7 elements ( Mn , Tc , Re ).
It can be synthesized from the reaction between rhenium and sulfur at 1000 °C, or the decomposition of rhenium(VII) sulfide at 1100 °C: [4] Re + 2 S → ReS 2 Re 2 S 7 → 2 ReS 2 + 3 S. Nanostructured ReS 2 can usually be achieved through mechanical exfoliation, chemical vapor deposition (CVD), and chemical and liquid exfoliations. Larger ...
Pages in category "Rhenium compounds" The following 29 pages are in this category, out of 29 total. This list may not reflect recent changes. O. Organorhenium chemistry;
Rhenium(VII) oxide is the inorganic compound with the formula Re 2 O 7. This yellowish solid is the anhydride of HOReO 3. Perrhenic acid, Re 2 O 7 ·2H 2 O, is closely related to Re 2 O 7. Re 2 O 7 is the raw material for all rhenium compounds, being the volatile fraction obtained upon roasting the host ore. [2]
Spectral lines of rhenium: Other properties; Natural occurrence: ... Hypothetical chemical elements (75) Subtemplates. These subtemplates are used automatically; they ...