The potential difference between a potassium ion and saturated calomel electrode immersed in 100.0 ml of 1.073 x 10 M KCI was 362 mV. When 594 mg of NH4CI was added to the KCI solution (no volume change), the potential difference was 386 mV. Calculate the selectivity coefficient kx*,NH, for K* over NH4. Assume that there is no loss of NHa due to acid-base equilibrium effects.

The potential difference between a potassium ion and saturated calomel electrode immersed in 100.0 ml of 1.073 x 10 M KCI was 362 mV. When 594 mg of NH4CI was added to the KCI solution (no volume change), the potential difference was 386 mV. Calculate the selectivity coefficient kx,NH, for K over NH4. Assume that there is no loss of NHa due to acid-base equilibrium effects.

Principles of Instrumental Analysis

7th Edition

ISBN:9781305577213

Author:Douglas A. Skoog, F. James Holler, Stanley R. Crouch

Publisher:Douglas A. Skoog, F. James Holler, Stanley R. Crouch

Chapter25: Voltammetry

Section: Chapter Questions

Problem 25.13QAP

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