Search results
Results from the WOW.Com Content Network
This compound reacts with water to produce perrhenic acid and nitric acid. [1] When heated above 75 °C, it decomposes to rhenium heptoxide, nitrogen dioxide, and oxygen: [1] 4 ReO 3 NO 3 → 2 Re 2 O 7 + 2 NO 2 + O 2. A graphite intercalation compound can be produced by reacting a mixture of rhenium trioxynitrate and dinitrogen pentoxide with ...
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
The high-temperature stability is also improved. The effect increases with the rhenium concentration, and therefore tungsten alloys are produced with up to 27% of Re, which is the solubility limit. [65] Tungsten-rhenium wire was originally created in efforts to develop a wire that was more ductile after recrystallization.
Rhenium trioxide is insoluble in water, as well as dilute acids and bases. Heating it in base results in disproportionation to give ReO 2 and ReO − 4, while reaction with acid at high temperature affords Re 2 O 7. In concentrated nitric acid, it yields perrhenic acid. Upon heating to 400 °C under vacuum, it undergoes disproportionation: [2]
Rhenium(IV) oxide or rhenium dioxide is the inorganic compound 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.
These salts are prepared by oxidation of rhenium compounds with nitric acid followed by neutralization of the resulting perrhenic acid. [2] [3] [4] Addition of tetrabutylammonium chloride to aqueous solutions of sodium perrhenate gives tetrabutylammonium perrhenate, which is soluble in organic solvents. [5]
Rhenium(VII) oxide can be formed when rhenium or its oxides or sulfides are oxidized a 500-700 °C in air. [24] It dissolves in water to give perrhenic acid. Heating Re 2 O 7 gives rhenium(IV) oxide, signalled by the appearance of the dark blue coloration. [25] In its solid form, Re 2 O 7 consists of alternating octahedral and tetrahedral Re ...
Perrhenic acid is the chemical compound with the formula Re 2 O 7 (H 2 O) 2.It is obtained by evaporating aqueous solutions of Re 2 O 7.Conventionally, perrhenic acid is considered to have the formula HReO 4, and a species of this formula forms when rhenium(VII) oxide sublimes in the presence of water or steam. [2]