HYDROLYSIS OF THE URANYL(VI) ION - A CHEMOMETRIC APPROACH

23 UV-Vis spectra of U(VI) samples in the pH range 2.9 to 4.8 and U(VI ) concentration range 10(-2) M to 310(-4) M are analysed by chemometr ic methods, e.g. abstract factor analysis (AFA), target factor analysi s (TFA) and target iteration. Decisions during analysis are made in te rms of statistical tests, e.g. scree test, Bartlett's chi(2) criteria or theory of error in TFA. From the analysis, a single component spect rum of the (UO2)(2)(OH)(2)(2+) species is evaluated, validated by targ et testing and applied in spectral analysis of 10 two-component UV-Vis spectra, resulting in a formation constant Ig K-22 = -6.14+/-0.08 and a molar absorption epsilon(22) = 101+/-2 1 mol(-1) cm(-1) at 421.8 nm .