Peroxy chromates

Analytical Delicate qual tests for H202 are its reactions with titanic chromate or sulfate in acid to produce the bright blue peroxychromic or bright yellow peroxy titanic acid both of which are sol in ether. Quantitatively H202 may be detd by its oxidation of I- and titration of the I2 (or I3) thus formed (Ref 2)... 

Oxidation states of chromium - -2, - -3, and -f-6. Oi es of chromium chronate, FeCr204, and crocoite, PbCr04. Chromium metal and its alloys ferrochrome, alloy steels, stainless steel. The aluminothermic process (Goldschrtiidt process). Electrolytic chromium. Chromium trioxide, chromic acid, dichromic acid, potassium chromate, potassium didiromate, sodium chromate, lead chromate. Equilibrium between chromate ion and dichromate ion. Chrome-tanned leather. Chromic oxide (chrome green) chromic ion, chrome alum, chromic chloride, chromic hydroxide, chromite ion. Chromous compounds. Peroxy-chromic acid. 

Methods based on iodine titration with thiosulfate Iodide, being a weak reduc-tant, can react with an enormous variety of oxidants to liberate an equivalent quantity of I2 that can be titrated with thiosulfate. Such oxidants include peroxides, peroxy compounds, peroxydisulfate, ozone, iron(III), chromate, selenium (as Se03 ), silver(II) oxide, xenon trioxide, iodate, and bromate. Bromide can be determined by oxidizing it to bromine, followed by extraction and determination of the bromine... 

For many years, sulfuric acid—dichromate mixtures wo-e used to clean glassware (a sulfuric acid—peroxy-disulfate solution is now recommended because disposal of chromate is a problem). Confusion about cleaning baths... 

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