Question

6. For each reaction listed, determine its standard cell potential at 25⁰C and whether the reaction is spontaneous at standard conditions. You will need to use Appendix L.

(a) Mg(s) + Ni²⁺(aq) ---> Mg²⁺(aq) + Ni(s)

(b) 3Fe²⁺(aq) + Au³⁺(aq) ---> 3Fe³⁺(aq) + Au(s)

(c) Cu(s) l Cu²⁺(aq) II Au³⁺(aq) I Au(s)

7. Determine the standard free energy change (DG⁰) in kJ for the reactions in question 6.

(a)

(b)

(c)

Answer 1

6. The standard cell potential is given by the following equation.

Here is the standard electrode potential of the electrode where reduction reaction occurs.

is the standard electrode potential of the electrode where oxidation reaction occurs.

Also

Here is the standard electrode potential of the right hand electrode.

is the standard electrode potential of the left hand electrode.

(a)

Since the reaction is spontaneous.

(b)

Since the reaction is spontaneous.

(c)

Since the cell reaction is spontaneous.

7.

(a)

(b)

(c)