Abstract: | Abstract A detailed investigation has been made of Che pH versus light absorption curves of solutions of PAR and Rh(III) in various concentrations. It has been shown, that depending on tile acidity of the solution, two different substances will be formed; the optimal conditions of the formation of each substance has been found. The molar absorptivities have been determined and the equilibrium and stability constants of the formed substances have been computed from the absorbance versus pH curves. |