Electromigration of carrier-free radionuclides

Dependences of La(III) overall ion mobilities on concentrations of ox^2– and tart^2– anions of oxalic and tartaric acid in aqueous solutions of 0.01 overall ionic strength and temperature 298.1 K were obtained by direct measurements of electromigration of carrierfree¹⁴⁰La-lanthanum(III). Concentration stability constants K_n and individual ion mobilities u _i ^o of oxalate and tartrate complexes of La(III) have been calculated for nitrate and perchlorate electrolytes, respectively: La(ox)]⁺, lg K₁=5.63(9), u⁰La(ox)]⁺=1.95(15)·10^–4 cm²·s^–1·V^–1; la(ox)₂]^–, lg K₂=4.05(19) u⁰La(ox)₂]^–=–1.76(20)·10^–4 cm²·s^–1·V^–1; La(tart)]⁺, lg K₁=4.40(5), u⁰La(tart)]⁺=+1.99(18)·10^–4 cm²·s^–1·V^–1.Results are compared with literature data. Additional, limiting individual La³⁺ ion mobility was calculated: =+6.9(1)·10^–4 cm²·s^–1·V^–1 for pure water at 298.1 K.