ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Use of acyl derivatives of 2,4-dinitrophenylhydrazine as acid-base indicators

A. Berkovič, E. Sidóová, and P. Majer

Institut für analytische Chemie an der Slowakischen Technischen Hochschule, Bratislava 1

Abstract: Some acyl derivatives of 2,4-dinitrophenylhydrazine were described and the possibility to use them as acid-base indicators was examined. Spectrophotometry measurements were recorded in ultraviolet, visible and infrared range and the pK_i values were determined. pH Regions for the change of colour of the investigated substances were established basing upon pH-metric titrations. It has been found that the change in colour is sharp enough and the substances are convenient for titrations of weak acids in the dissociation constant range K= 10^-4 — 10^-6. The influence of nitro groups upon the change of colour is discussed.

Full paper in Portable Document Format: 241a38.pdf (in German)

Chemical Papers 24 (1) 38–45 (1970)