A Simple Determination of the Ag₂O Solubility Product by Potentiometric Determinations of Both Ag⁺¹ and OH^–1

Abstract

A simple determination of the Ag2O solubility product, Ksp, suitable for introductory, analytical, or physical chemistry courses is presented. Two pH meters are required and 10-4 mol of AgNO3 or AgOAc is consumed. The concentration cell, Ag(s) | Ag+ (0.001 M) || Ag+ (0.001 M) {pH electrode} | Ag(s), is used. The cell potential and pH are monitored as standard 0.1 M NaOH is titrated into the cathode compartment, precipitating Ag2O. The cathode pOH, pAg, and pKsp are computed at each point of the titration. The results illustrate theoretical expectation and are in excellent agreement with the literature.