Potentiometric Titration Based on the Reference Electrode Equipped with Ionic Liquid Salt Bridge — 1. Precipitation Titration of Chloride with Silver Ions in Water (Supporting Information)
posted on 2022-12-06, 08:29authored byTakashi KAKIUCHI, Ryunosuke TANIGO, Atsushi TANI, Takeshi YAMAZAKI, Kohta KOMATSUBARA, Keiji NAKANO, Masahiro YAMAMOTO
<p>A reference electrode equipped with ionic liquid salt bridge consisting of tributyl(2-methoxyethyl)phosphonium bis(pentafluoroethanesulfonyl)amide has been employed for potentiometric precipitation titration of chloride with silver ions in water at 25 °C. A model for the titration curve was regressed to experimental curves, taking into account the change in the activity coefficients of relevant ionic species in the course of the titration, to obtain the least square estimates of two adjustable parameters in the model, the solubility product (<i>K</i><sub>sp</sub>) and the analyte concentration. The least-square estimate of <i>K</i><sub>sp</sub>, (1.840 ± 0.060) × 10<sup>−10</sup>, i.e., p<i>K</i><sub>sp</sub> = 9.736 ± 0.014, is in good agreement with literature data, but with higher precision.</p>
Funding
Fundamental Basis for New Methods of Separation and Analysis Based on the Control of Electrical Potential at Ionic Liquid| Solution Interface
Formulation of the basis for measuring ion activity in concentrated aqueous solutions and its application to high precision measurements of ocean acidification