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# Half Cell Reaction, standard Potential, Free Energy

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The reaction between silver ion and solid zinc is represented by the following equation.

2 Ag+ (aq) + Zn(s) ---> Zn2+(aq) + 2Ag(s)

(a) A 1.50 sample of Zn is combined with 250 ml of 0.110 M AgNO3 at 25oC.
(ii) On the basis of limiting reactants that you identified in part (i), determine the value of the [Zn2+] after the reaction is complete. Assume that volume change is negligible.

(b) Determine the value of the standard potential, Eo, for a galvanic cell based on the reaction between AgNO3(aq) and solid Zn at 25 C.

Another galvanic cell is based on the reaction between Ag+(aq) and Cu(s), represented by the equation below. At 25 C, the standard potential, Eo, for the cell is 0.46 V.

2 Ag+ (aq) + Cu(s) ---> Cu2+(aq) + 2Ag(s)

(c) Determine the value of the standard free-energy change, deltaGo, for the reaction between Ag+ (aq) and Cu(s) at 25 C.

(d) The cell is constructed so that [Cu2+] is 0.045 M and [Ag+] is 0.010 M. Calculate the value of the potential E for the cell.

(e) Under the conditions specified in part (d), is the reaction in the cell spontaneous? Justify your answer.