Abstract

Visible Spectrum Of The Copper(II)-Thiosuphate Complex

Author(s): Unguresan Mihaela Ligia, Niac Gavril

Spectrum between 700nm and 360nm of the short-lived, colored, CuS2O3 intermediate complex was determined using a stopped-flow method with 0.005mol/l concentrations of Cu2+ and thiosulfate at 28.30C. The concentration of the complex was considered equal to that of Cu2+ in a special run at Cu2+ and thiosulfate concentrations of 0.00173mol/l and 0.18mol/ l respectively. The start of the redox reaction 2 CuS2O3 → 2 Cu+ + S4O6 2– was moved into the time scale of the oscilloscope, reoxidizing Cu+ by addition of 0.02mol/l Fe3+ until complete reduction of Fe3+ to Fe2+ (a Landolt type process).