Polarometric determination of aromatic aldehydes with 2,4-dinitrophenylhydrazine

Abstract

In the polarometric titration of aromatic aldehydes with a 2,4-dinitrophenylhydrazine solution, the sorption of the reagent on the hydrazone precipitate and the reduction of this precipitate at the mercury dropping electrode have been proved. These effects may be eliminated by the addition of thymol or ethanol to the sample solution, so that most aromatic aldehydes can be determined.