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Half Cell Reaction, standard Potential, Free Energy

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.
(i) Identify the limiting reactant. Show calculations to support your answer.
(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.

Solution Summary

Half Cell Reactions, Standard Potentials, Free Energy, and Limiting Reagents are investigated. The solution is detailed and well presented.