Short communication, Note

Kinetics of Reduction of Aza Cyanine Dyes by Bisulphite Ions in (Acetate-Acetic Acid) Buffer-Ethanol Mixtures

M. M. Girgis ; Chemistry Department, Faculty of Science, Assiut University, Assiut, Egypt
A. S. EI-Shahawy ; Chemistry Department, Faculty of Science, Assiut University, Assiut, Egypt
Z. H. Khalil ; Chemistry Department, Faculty of Science, Assiut University, Assiut, Egypt

Abstract

The kinetics of bisulphite ions reduction of 2-[[[4-(dimethylamino)
phenyl]imino]methyl]-l-ethylpyridinium iodide (I), 4-[[[4-
-(dimethylamino)phenyl]imino]methyl]-l-ethylpyridinium iodide
(II) and 2-[[[4-(dimethylamino)phenyl]imino]methyl]-1-ethylquin0-
linium iodide (III) in buffer- ethanol mixtures were investigated
from 18ce to 45ce spectrophotometrically. These reactions follow
the overall second-order kinetics, first order with respect to each
of the reactants. Reaction rates decrease with increasing ethanol, as
well as hydrogen ion concentrations. The reduction rate (k2) of aza
cyanine dyes depends on the structure of the dye used and follows
the order: dye(I) > dye(lI) > dye(III). Activation parameters were
evaluated using Arrhenius and Eyring equations.

Keywords

Hrčak ID:

176396

URI

https://hrcak.srce.hr/176396

Publication date:

23.12.1987.

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