A lithium ion-selective electrode gave the potentials given below for the following standard solutions of LiCl and two samples of unknown concentration: Solution (aµ-) Potential vs. SCE, mV 0.100 M +1.0 0.050 M -30.0 0.010 M -60.0 0.001 M - 138.0 Unknown 1 -48.5 Unknown 2 -75.3 (a) Construct a calibration curve of potential versus log a+ and determine if the electrode follows the Nernst equation. (b) Use a linear least-squares procedure to determine the concentrations of the two unknowns.

A lithium ion-selective electrode gave the potentials given below for the following standard solutions of LiCl and two samples of unknown concentration: Solution (aµ-) Potential vs. SCE, mV 0.100 M +1.0 0.050 M -30.0 0.010 M -60.0 0.001 M - 138.0 Unknown 1 -48.5 Unknown 2 -75.3 (a) Construct a calibration curve of potential versus log a+ and determine if the electrode follows the Nernst equation. (b) Use a linear least-squares procedure to determine the concentrations of the two unknowns.

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter21: Potentiometry

Section: Chapter Questions

Problem 21.29QAP

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