Carbazide diphenylcarbazide

Diphenylcarbazide (1 % alcoholic solution). Dissolve 010 g sy/w.diphenyl-carbazide, (CgHs.NH,NH)2CO, in 10 ml of 96% ethanol. The solution decomposes rapidly if exposed to air. 

Diphenylcarbazide (0-2% solution with acetic acid). Dissolve 0 2 g sym. diphenyl carbazide, (C6H5.NH.NH)2CO, in 10 ml glacial acetic acid and dilute the mixture to 100 ml with ethanol. 

Diphenylcarbazide (DPC) solution Dissolve 250 mg of 1,5-diphenyl-carbazide in 50 mL acetone. Store in an amber bottle. Discard when the solution becomes discolored. 

Strong acid solutions of chromates react with diphenylcarbazide(I) to give a violet coloration, even though only traces of chromium are present. It is claimed that the color reaction involves an action that has not been observed in other cases the chromate, in acid solution, oxidizes diphenyl-carbazide (I) initially to colorless diphenylcarbazone (II) and then to light yellow diphenylcarbadiazone (III) ... 

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