Original scientific paper

Methorics of the Precipitation Processes. XX. Silver Salts of Dyes of the Fluorescein Group (Fluorescein, Eosin, and Erythrosin) in Aqueous Medium

E. Palić-Schutz ; Laboratory of Physical Chemistry, Faculty of Science, University of Za,greb, Zagreb, Croatia, Yugoslavia
Đ. Težak ; Laboratory of Physical Chemistry, Faculty of Science, University of Za,greb, Zagreb, Croatia, Yugoslavia
B. Težak ; Laboratory of Physical Chemistry, Faculty of Science, University of Za,greb, Zagreb, Croatia, Yugoslavia

Abstract

The precipitation systems consisting of aqueous solutions
of silver nitrate and the dyes of the fluorescein group (fluorescein,
eosin, and erythrosin) have been investigated by means of tyndallometric
measurements by systematically varying the concentration
of the precipitating components. The general and three-
dimensional precipitation diagrams of the »precipitation bodies«
show very characteristic features. The silver fluoresceinate shows
two regions; the precipitation region and the region of clear
systems are divided by a straight line with the slope indicating
the formation of Ag2-fluoresceinate in accordance with the ionic
solubility law. The silver eosinate systems show two precipitation
regions divided by a narrow region of clear systems. With respect
to both the limits of the clear equivalency region and the two precipitation regions, the silver erythrosinate systems are even more
specific. An attempt has been made to give an explanation for the
negative charges of primary particles in spite of the large excess
of silver ion, as well as for the characteristic shape of the »precipitation
bodies«.

Keywords

Hrčak ID:

208301

URI

https://hrcak.srce.hr/208301

Publication date:

30.12.1964.

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