The reduction potential of Ag^+|(aq) to Ag(s) is +0.80 V, and the reduction potential of Cu^2+ (aq) to Cu (s) is + 0.34 V. A galvanic cell is based on the following reaction:
2 Ag^+ (aq) + Cu (s) -----> 2 Ag (s) + Cu^2+ (aq)
The silver compartment contains a silver electrode and excess AgCl(s) (Ksp = 1.6 x 10^-10) which gives a silver ion concentration of 1.27 x 10^-5 M. The copper compartment contains a copper electrode and [Cu^2+] = 2.0 M.
a) Claculate the potential for this cell, Ecell, at 25 degree Celsius.
b) Can a reaction be spontaneous at 298 K when its delta Grxn (298 K) is positive?
Explain.
c) A reaction taking place under standard conditions is sponteneous at 1000 K but is nonsponteneous at 300 k. What are the signs of delta Hrxn and delta S rxn?