Bichromate anion

The various simple chromate anions including chromate, Cr042-, dichromate, Cr2072, and bichromate, HCr04, have all been reported to be potent corrosion inhibitors when they are present as soluble species in solution. Chromate is an effective inhibitor for Al, Fe, Mg, Cd, Sn, and many other metals and alloys. The specific form of the anion present in solution depends on its concentration and solution pH (21). Because evidence of corrosion inhibition has been detected over very wide ranges of soluble Cr(VI) ion concentration and pH, each of these species appears to possess inhibiting properties. 

The relationship between chemical composition of the oxidizer and the burning time of the sawdust has been determined by Uehara. The results are shown in Table 3.18. The trend in burning rate is tabulated as a function of the anion. The order of the burning rate of sodium salts is chlorite > peroxide > bromate > chlorate > nitrite > iodate > perchlorate > nitrate > bichromate. 

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