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Niobium pentoxide is the inorganic compound with the formula Nb 2 O 5. A colorless, insoluble, and fairly unreactive solid, it is the most widespread precursor for other compounds and materials containing niobium. It is predominantly used in alloying, with other specialized applications in capacitors, optical glasses, and the production of ...
Niobium forms oxides in the oxidation states +5 (Nb 2 O 5), [77] +4 (NbO 2), and the rarer oxidation state, +2 . [78] Most common is the pentoxide, precursor to almost all niobium compounds and alloys. [61] [79] Niobates are generated by dissolving the pentoxide in basic hydroxide solutions or by melting it in alkali metal oxides.
Niobium oxide, archaically called columbium oxide, [1] may refer to: Niobium monoxide (niobium(II) oxide), NbO; Niobium dioxide (niobium(IV) oxide), NbO 2; Niobium pentoxide (niobium(V) oxide), Nb 2 O 5; In addition to the above, other distinct oxides exist general formula Nb 3n+1 O 8n−2 where n ranges from 5 - 8 inclusive, e.g. Nb 8 O 19 (Nb ...
Lithium niobate (Li Nb O 3) is a synthetic salt consisting of niobium, lithium, and oxygen. Its single crystals are an important material for optical waveguides, mobile phones, piezoelectric sensors, optical modulators and various other linear and non-linear optical applications. [6] Lithium niobate is sometimes referred to by the brand name ...
The niobate can be obtained by reacting niobium pentoxide with the corresponding oxide, hydroxide or carbonate. [1] For example, reacting lithium carbonate with niobium pentoxide would obtain lithium niobate: [2] Li 2 CO 3 + Nb 2 O 5 → 2 LiNbO 3 + CO 2 ↑. Cobalt metaniobate can be obtained by heating a mixture of cobalt monoxide and niobium ...
Phosphorus pentoxide is a potent dehydrating agent as indicated by the exothermic nature of its hydrolysis producing phosphoric acid: P 4 O 10 + 6 H 2 O → 4 H 3 PO 4 (–177 kJ) However, its utility for drying is limited somewhat by its tendency to form a protective viscous coating that inhibits further dehydration by unspent material.
Niobium(V) can form complexes with hydroxy acids, as well as oxalic acid. The salt formed is more complex than tartaric acid for niobium (as opposed to tantalum). [3] NH 4 [NbO(C 2 O 4) 2 (H 2 O) 2]·3H 2 O starts to lose water at 125°C, and at 630°C, it fully decomposes, forming a compound known as niobium pentoxide; [4] Heating this complex and sodium citrate at 650°C can form sodium ...
The salt is prepared by dissolving niobium pentoxide in a solution of potassium bifluoride in 40% hydrofluoric acid: [4] Nb 2 O 5 + 4 KHF 2 + 6 HF → 2K 2 NbF 7 + 5 H 2 O. Potassium heptafluoroniobate and potassium heptafluorotantalate are isostructural. The anion has approximate C 2v symmetry, being a face-capped trigonal prism. The Nb-F ...