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Vanadyl ions oxidation

The 4-4 oxidation state, which for Nb and Ta is best represented by their halides, is most notable for the uniquely stable VO + (vanadyl) ion which retains its identity throughout a wide variety of reactions and forms many complexes. Indeed it is probably the most stable diatomic ion known. The M ions have only slightly smaller radii... [Pg.979]

In the higher oxidation states partially hydrolysed species dominate the aqueous chemistry, the most important being the oxovanadium(IV), or vanadyl, ion This gives the sul-... [Pg.993]

Table 3 Redox potentials (V vs. SCE) for the one-electron oxidation of Schiff base complexes of vanadyl ion... Table 3 Redox potentials (V vs. SCE) for the one-electron oxidation of Schiff base complexes of vanadyl ion...
The +4 oxidation state is the most stable under ordinary conditions and the majority of vanadium(IV) compounds contain the V02+ unit (vanadyl ion), which can persist through a variety of reactions. Its complexes typically have square pyramidal or bipyramidal geometry... [Pg.455]

The electrostatic modd for the hydrated vanadyl ion consists of V,+ situated in a tetragonal dectric fidd caused by the oxide ion and five water dipoles. The ctystal fidd energy levd diagram for such a situation is given in Fig. 1. [Pg.227]

Vanadate is reduced in red cells to vanadyl ion by intracellular glutathione following uptake through a phosphate transport system.1072,1073 Free vanadyl is normally unstable with respect to oxidation, but appears to be stable when complexed with intracellular proteins or smaller molecules.1074 Vanadyl ion is a relatively powerful inhibitor of (Na+, K+)-ATPase. For pure fractions of the enzyme, inhibition was nearly complete at less than 5 pmol dm-3 vanadyl ion.1075 The state of vanadyl ion at pH 7 is somewhat uncertain, but may involve a hydroxylated species. Vanadyl ion also inhibits alkaline phosphatase more effectively than does vanadate.1076... [Pg.665]

Smits, Seshan and Ross have studied the selective oxidative dehydrogenation of propane to propylene over Nb20s and Nb2C>5 supported on alumina.32 Vanadia supported on MgO has typically been used in these reactions, although reduced surface vanadyl ions can give rise to decreasing selectivity to propylene. Niobia on the other hand, is much more difficult to reduce than vanadyl but there have been few studies with this oxide in such reactions. [Pg.19]

The IV State. This is the most important oxidation state of Ti, and the main chemistry is that of Ti02 and TICL and its derivatives. It is also an important state for vanadium, which forms the vanadyl ion VO2 and many derivatives, cationic,... [Pg.694]

Vanadium (V, at. mass 50.94) occurs in the V, IV, III, and II oxidation states, vanadium(V) compounds being the most stable. In alkaline medium, the colourless vanadate VOs ions exist, whereas in strongly aeidic media, the yellow V02 cations are present. Within the intermediate pH range polymerized orange-yellow anionic forms occur. Vanadium(V) forms heteropoly acids with P(V), Mo(VI), and W(VI), and also peroxide complexes. Vanadium(IV) occurs as the blue vanadyl ion V02", stable in acid solutions and readily oxidized to vanadium(V) in alkaline solution. The VO cation is amphoteric. At pH 4, V0(0H)2 precipitates and at pH 9 it dissolves. Vanadium(IV) forms fluoride-, oxalate-, and... [Pg.456]

Vanadium has a relative abundance of about 0.02 %. Oxidation states of V to I are known. Vanadium solutions generally contain several species in a complicated series of equilibria. V(V) and V(IV) are both stable, with the former mildly oxidizing and represented mainly by oxy species. Pervanadyl ion (VO2 ) is a major species in strongly acidic solutions, while in strong base, the mononuclear vanadate, VOa exists. V(IV) ions are stable in acid, and give blue solutions of vanadyl ion (VO ). A number of anions of the IV oxidation state are known, including VOj ", and V409 . These ions are stable under alkaline conditions. [Pg.236]


See other pages where Vanadyl ions oxidation is mentioned: [Pg.982]    [Pg.245]    [Pg.782]    [Pg.275]    [Pg.24]    [Pg.837]    [Pg.227]    [Pg.902]    [Pg.816]    [Pg.224]    [Pg.155]    [Pg.222]    [Pg.527]    [Pg.49]    [Pg.149]    [Pg.5032]    [Pg.5461]    [Pg.837]    [Pg.505]    [Pg.103]    [Pg.336]    [Pg.217]    [Pg.816]    [Pg.824]    [Pg.547]    [Pg.706]    [Pg.12]    [Pg.74]    [Pg.16]    [Pg.45]    [Pg.91]    [Pg.171]    [Pg.187]    [Pg.32]    [Pg.926]    [Pg.982]    [Pg.993]    [Pg.595]   
See also in sourсe #XX -- [ Pg.501 ]

See also in sourсe #XX -- [ Pg.3 , Pg.501 ]




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Vanadyl

Vanadyl ions

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