A 25.0 mL solution of 0.0640 M Fe2* in 1 M HNO3 was titrated with 0.0500 M Pb4+ to give Fe3+ and Pb2+. Write the relevant half reactions and standard potentials. a) Calculate the potential (vs. S.C.E.) when 11.5 mL of titrant is added. b) Calculate the potential (vs. S.C.E.) at the equivalence point. c) Calculate the potential (vs. S.C.E.) when 18.5 mL of titrant is added. d) At what volume of analyte will the potential be equal to the standard potential of the Pb half-reaction (ignoring S.C.E.)?

A 25.0 mL solution of 0.0640 M Fe2* in 1 M HNO3 was titrated with 0.0500 M Pb4+ to give Fe3+ and Pb2+. Write the relevant half reactions and standard potentials. a) Calculate the potential (vs. S.C.E.) when 11.5 mL of titrant is added. b) Calculate the potential (vs. S.C.E.) at the equivalence point. c) Calculate the potential (vs. S.C.E.) when 18.5 mL of titrant is added. d) At what volume of analyte will the potential be equal to the standard potential of the Pb half-reaction (ignoring S.C.E.)?

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

Chapter23: Potentiometry

Section: Chapter Questions

Problem 23.24QAP

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