A potentiometric titration of a 0.278 g sample of FeSO4.7H₂O salt, in acidic medium, with a 0.011 M solution of potassium dichromate (K,Cr:O) was conducted. Cr₂0 + 6 Fe + 14 H → 2Cr + 6 Fe" + 7 H₂O The potential is measured with respect to a calomel electrode (E-246 mV). Graph 1 represents the measured potential with respect to the volume of added dichromate. Calculate E for the half-reaction: Fe + e-Fe (Show your work using Nernst equation). Hint: Use the graph, to determine, approximately, the equivalence point and mid-point of the titration

A potentiometric titration of a 0.278 g sample of FeSO4.7H₂O salt, in acidic medium, with a 0.011 M solution of potassium dichromate (K,Cr:O) was conducted. Cr₂0 + 6 Fe + 14 H → 2Cr + 6 Fe" + 7 H₂O The potential is measured with respect to a calomel electrode (E-246 mV). Graph 1 represents the measured potential with respect to the volume of added dichromate. Calculate E for the half-reaction: Fe + e-Fe (Show your work using Nernst equation). Hint: Use the graph, to determine, approximately, the equivalence point and mid-point of the titration

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

Chapter24: Coulometry

Section: Chapter Questions

Problem 24.12QAP

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