The hydrolysis of Y3+, La3+, Gd3+ and Er3+ ions in an aqueous solution containing 3 M (Li)ClO4 as an ionic medium

Abstract The hydrolysis equilibria of Y3+, La3+, Gd3+, and Er3+ ions have been studied at 25°C in 3 M (Li)ClO4 by measuring the hydrogen-ion concentration with a glass electrode. All the test solutions containing hydrolyzed species prepared by the addition of alkali were acidified by means of constant-current coulometry. The data, which indicate a slight hydrolysis of the relevant ions, can be explained by assuming the formation of the following complexes: Y(OH)2+, logβ2,1=−17.0±0.1; Y2(OH)24+, logβ2,2=−14.04±0.01; LaOH2+, logβ1,1=−10.04±0.01; GdOH2+, logβ1,1=−8.20±0.01; Er(OH)2+, logβ2,1=−17.4±0.1; Er2(OH)24+, logβ2,2=−13.72±0.01.