I and Chromium II

The redox chemistry of the relatively stable (hours) Cr(I) complex [Cr (NO- )(OH2)5] + [e(449) = 120] has been explored with U(III) as a reducing agent k = 49 s-1, to give hydroxylamine) and excess bromate 

More conventional studies (Table 6.13) involve the reaction of r(II) with hydroxylamine-O-sulfonic acid (NHjOSO3 [(NH3)5 o-N = 

The rate profiles, stoichiometry, and reaction product distributions are often extremely complicated. Thus, for the seemingly innocent [ o(bpy)3] plus r reaction, there are four consecutive rate steps that can be observed and the product mixture contains [ r2(bpy)(OH)2(OH2)6] , [ o(OH2)6] - , [ o(bipy)(OH2)4], bpy, and reduced bpy. In many cases, radical-ion mechanismsare involved, accounting for the observed complexities. 

Nevertheless, the rate of thermal decomposition of [(mhpa)2CrO] has been investigated as well as the kinetics of [(ehba)2CrO] with [Mo(V)204] , benzyl alcohols, imsaturated alcohols, [IrClg] , lactic acid, thiolactic add, and rac-tartaric add.  

The spectroscopy of Cr(VI) systems has been reviewed, raising again the issue of the existence or otherwise of the bichromate ion, HCrOj. Many authors dealing with the kinetics of Cr(VI) oxidation in aqueuos add solution attribute the add dependence to the formation of HCrO and, if this species is not present, then considerable mechanistic revision will be required. Thermodynamic properties of the HCrO ion have been estimated but 

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