Dithizone, diphenylthiocarbazone

Theory In solution, dithizone (diphenylthiocarbazone) exhibits tautomerism as shown below ... 

Dithizone (diphenylthiocarbazone) is a green compound that is soluble in nonpolar organic solvents and insoluble in water below pH 7. It forms red, hydrophobic complexes with most di- and trivalent metal ions. 

Dithizone Indicator Solution Dissolve 10 mg of dithizone (diphenylthiocarbazone) with acetone in a 10-mL volumetric flask, and fill to volume. 

Dithizone (Diphenylthiocarbazone) A blue-black powder. Insoluble in water soluble in alcohol and in chloroform, yielding intensely green solutions even in high dilutions. 

All observed interferences, except those due to antimony, gold(III) and nitrite, were masked by the pumped addition of 0.02MEDTA (the pH adjusted to 3 with dilute hydrochloric acid) to the sample prior to the reduction step. In the presence of a 5000-fold excess of iron(III), however, depression of the dimethylarsenic signal cannot be completely restored by EDTA (Table 5). Extraction of the sample solution (at pH 2.0) with a 0.005 M solution of dithizone (diphenylthiocarbazone) in dichloromethane overcomes interferences due to silver(I), gold(III), chromium(VI), molybdenum(VI) and tin(II). 

When determining zinc with dithizone (diphenylthiocarbazone) red zinc dithizonate is formed ... 

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