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Nernst Equation problems

You are titrating 100.0 mL of 0.0400 M Fe^2+ in 1 M HClO_4 to give Fe^3+ and Ce^3+ using Pt and calomel electrodes to find the endpoint.

a)
Write the balanced titration reaction.

Ce^4++Fe^2+ Ce^3++Fe^3+

Complete the two half reactions for the Pt electrode.
Ce^4+ + e^- Ce^3+ + e^- E^0 = 1.70 V
Fe^2+ + e^- Fe^3+ +e^- E^0 = 0.767 V

b)
From the list select the two correct Nernst equation for the cell
a. E = 0.767- 0.05916log([Fe^2+]/[Fe^3+]-0.241
b. E = 0.767- 0.05916log([Fe^3+]/[Fe^2+]-0.241
c. E = 1.70- 0.05916log([Fe^2+]/[Fe^3+]-0.241
d. E = 1.70- 0.05916log([Fe^3+]/[Fe^2+]-0.241
e. E = 0.767- 0.05916log([Ce^3+]/[Ce^4+]-0.241
f. E = 0.767- 0.05916log([Ce^4+]/[Ce^3+]-0.241
g. E = 1.70- 0.05916log([Ce^3+]/[Ce^4+]-0.241
h. E = 1.70- 0.05916log([Ce^4+]/[Ce^3+]-0.241

c)
Calculate the values of E for the cell when the following volumes of the Ce^4+ titrant have been added. (Activity coefficients may be ignored as they tend to cancel when calculating concentrations of ratios.

a. 1.50 mL
b. 20.0 mL
c. 39.0 mL
d. 40.0 mL
e. 44.0 mL
f. 80 mL

Solution Summary

A few problems based on Nernst equation are solved.

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