20. Electrochemistry

Calculate the standard cell potential of an electrolytic cell when given the following half reactions. 

Standard Reduction Potentials

Fe³⁺ (aq) + e ^– →  Fe²⁺ (aq)        E°_red = + 0.769 V

Li⁺ (aq) + e ^– →  Li (s)                  E°_red = – 3.04 V

Use the standard half-cell potentials listed below to calculate the standard cell potential for the following reaction occurring in an electrochemical cell at 25°C.  

3 Cl_2­ (g) + 2 Fe (s)  →  6 Cl ^– (aq) + 2 Fe³⁺ (aq)

Standard Reduction Potentials

Cl₂ (g) + 2 e^– →  2 Cl ^– (aq)                      E°_red = + 1.396 V
Fe³⁺ (aq) + 3 e^– →  Fe (s)                         E°_red = – 0.040 V

Predict whether the following reaction will occur as written based on the calculated E^ºcell. 

Ag⁺ (aq) + Au (s)  →  Ag (s) + Au³⁺ (aq)

Standard Reduction Potentials

Ag⁺(aq) + e^– →  Ag (s)                         E°_red = + 0.80 V
Au³⁺ (aq) + 3 e^– →  Au (s)                    E°_red = + 1.50 V