Solubility and acidic constants at 25 °C in NaClO4 aqueous solutions of 1-(2-hydroxyphenyl)ethanone

Abstract

The acid–base equilibria of 1-(2-hydroxyphenyl)ethanone (HY) were studied, at 25 °C, by potentiometric measurements with a glass electrode in NaClO4 media for ionic strength ranging from 0.51 to 3.5 mol/kg. The solubility (S) of HY was determined in the same range of ionic strength in NaClO4 media. The total concentration (C L) of ligand was ranged from 1 × 10−3 mol/kg to 20 × 10−3 mol/kg; the experimental data were explained by assuming, for HY, the species HY2 − besides Y−. Elaboration of data, according to the specific interaction theory, had provided the constants valid in the infinite dilution reference state: HY ⇄ Y− + H+, log K°1-1 = − 10.11 ± 0.05 and 2 HY ⇄ HY2 − + H+, log K°2–1 = − 7.85 ± 0.05. The uncertainties were given as 3σ. The interaction coefficients (kg/mol) of ionic species Y− and HY2 − with the medium counter ion were e (Y−, Na+) = 0.50 ± 0.05 and e (HY2 −, Na+) = 0.59 ± 0.05, respectively.