Response of an ion-selective electrode When a fluoride electrode was immersed in standard solutions (maintained at a constant ionic strength of 0.1 M with NaNO3), the following potentials (versus S.C.E) were observed: [F -1 (M) E (mV) 1. Add Sample. 2 Add Stabilizer (TISAB). 3. Stir (steady rate). 4. Insert electrode. 5. Measure. Measurement 1.00 x 10 -5 100.0 1.00 x 10 -4 41.5 Sanple 1.00 х 10 -3 -17.0 Because the ionic strength is constant, the response should depend on the logarithm of the F- concentration. Find [F - ] in an unknown that gave a potential of 0.0 mV.

Response of an ion-selective electrode When a fluoride electrode was immersed in standard solutions (maintained at a constant ionic strength of 0.1 M with NaNO3), the following potentials (versus S.C.E) were observed: [F -1 (M) E (mV) 1. Add Sample. 2 Add Stabilizer (TISAB). 3. Stir (steady rate). 4. Insert electrode. 5. Measure. Measurement 1.00 x 10 -5 100.0 1.00 x 10 -4 41.5 Sanple 1.00 х 10 -3 -17.0 Because the ionic strength is constant, the response should depend on the logarithm of the F- concentration. Find [F - ] in an unknown that gave a potential of 0.0 mV.

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter21: Potentiometry

Section: Chapter Questions

Problem 21.28QAP

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