Chapter 11, Problem 57E

The black silver sulfide discoloration of silverware canbe removed by heating the silver article in a sodiumcarbonate solution in an aluminum pan. The reaction is
${\text{3Ag}}_{\text{2}}\text{S(}s\text{)+2Al(}s\text{)}\rightleftharpoons \text{6Ag(}s{\text{)+3S}}^{\text{2–}}\text{(}aq{\text{)+2Al3}}^{\text{+}}\text{(}aq\text{)}$
a. Using data in Appendix 4, calculate $\Delta G°$, K, andfor the above reaction at 25°C. [For ${\text{Al}}^{\text{3+}}\text{(}aq\text{),}\Delta G_{\text{f}}^{°}\text{=-480}\text{. kJ/mol}$ .]
b. Calculate the value of the standard reduction potentialfor the following half-reaction:
${\text{2e}}^{\text{–}}{\text{+Ag}}_{\text{2}}\text{S(}s\text{)}\to \text{2Ag(}s{\text{)+S}}^{\text{2–}}\text{(}aq\text{)}$