Molybdenum complexes hydrogen peroxide determination

Molozonides see Primary ozonides Molybdenum(VI) complexes bimetallic complexes, 428 hydrogen peroxide determination, 635-6, 640... 

Early work on peroxo compounds of molybdenum has been reviewed.286 The stoichiometri-cally simplest Mo peroxo complex is the red-brown Mo(02)4 ion formed by the reaction of MoO2- with H202. Although the complex is not stable in solution and decomposes slowly with the evolution of 02, the anion can be crystallized as the Zn(NH3)4+ salt whose structure has been determined. In a sense, Mo(02)4 is an intermediate in the thermodynamically favored decomposition of hydrogen peroxide to water and oxygen. 

Bradfield and Stickland [40,41] determined molybdenum in plant tissue by its catalytic effect on the liberation of iodine from the reaction between potassium iodide and hydrogen peroxide. The detection limit is 0.003 pg/ml of molybdenum. Interference from iron and tungsten can be overcome by addition of ammonium fluoride, but for the greatest precision and accuracy a preliminary separation of molybdenum as its benzoin a-monoxime complex is recommended. 

Cr(VI). In acting as catalysts, these substances fonn complexes or peroxides, though complex formation in itself is not sufficient to produce catalysis. In basic solution, catalysts involve substances that are easily oxidized and reduced, such as Fe(II), Co(II), and Cu(II). As an example, Svehla and Erdey determined traces of molybdenum through its catalytic effect on the overall hydrogen peroxide-iodide reaction,... 

Chen, L. H. Liu, L. Z. Shen, H. X. Studies on mimic peroxidase behaviors of molybdenum(VI)-sodium dodecyl sulphate complex for the determination of hydrogen peroxide and glucose. Anal. Lett. 2004,37, 561-573. 

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