spectrophotometric study of the stoichiometry and conditional stability constants of some trivalent metal ion complexes of methylthymol blue

complexation reactions between methylthymol blue and fe , a l ,ga , 1n a nd ti ions have been studied in buffer aqueous solutions of ph 5.0 at 2s°c by a spectrophotometric technique. the conditional stepwise stability constants of the resulting 1:l and 1:2 (metal-to-ligand) complexes were determined from the absorbance-mole ratio data at three different wavelengths of the visible spectra. the overall stabilities of the resulting complexes vary in the order a l > fe > g a = 1n > t1 .