(a) Using Reactions 2 and 3, calculate E° and write the Nernst equation for the cell.

(b) Use the value of K_sp for A_gI to compute [Ag⁺] and find the cell voltage. By the reasoning in Figure 13-8, in which direction do electrons flow?

(c) Suppose, instead, that you wish to describe the cell with Reactions 1 and 3. We know that the cell voltage (E, not E°) must be the same, no matter which description we use. Write the Nernst equation for Reactions 1 and 3 and use it to find E° in Reaction 1.

Compare your answer with the value in Appendix H.

Figure 13-8

Electrons flow from Cd to Ag Cd?* | Cd Ag* | Ag E = 0.781 V E=-0.461 V -1.0 -0.5 0.5 1.0 E(cell) = 0.781 (-0.461) = 1.242 V