Reference no: EM131462100

The goal of this problem is to calculate the equilibrium constant for reaction (6) in the Experiment 4 handout: 2Cu2+(aq) + 5I-(aq) → 2CuI(s) + I3 -(aq)

a. The first task is to calculate E° for the following half-reaction, which is not given in Appendix H of Harris: Cu2+(aq) + I-(aq) + e- ? CuI(s) Show that this half-reaction can be written as a combination of a half-reaction that is in Appendix H and the (complete) reaction corresponding to the Ksp of CuI. [The result is a half-reaction so you are not trying to cancel the electrons.] Calculate E° for this half-reaction by combining E° values from question 1b and Appendix H.

b. Show that reaction (6) can be written as a combination of the half-reaction from part a and some other half-reaction from Appendix H. Calculate E° for the net redox reaction. Why do you not multiply E° for a half-cell by the same factor you used to balance the net reaction?

c. Finally, calculate K for reaction (6) at 25 °C. Is it safe to assume that this reaction should go to completion as written? What can you do experimentally to ensure that all the copper in your sample reacts?