Answer to Question #216887 in Inorganic Chemistry for Nick

Question

1.                                             Fe³⁺ + e^- → Fe²⁺   E^o = +0.77 V

        Fe²⁺ + 2e^- → Fe    E^o = -0.44 V

•  Using the redox reactions of iron represented above, draw a potential diagram that summarizes the redox chemistry of iron in an aqueous solution
• Calculate the value of E for the reduction of Fe³⁺(aq) to iron metal

Answer 1

The first half-reaction represents the reduction of iron (III) to iron (II). The second half-reaction represents the reduction of iron (II) to iron metal. We can find the reduction potential of our desired reaction by adding these two half-reactions and eliminating common species on both sides. The reduction potential of our desired reaction will then be the sum of the reduction potentials of these two half-reactions.

=0.77−0.44 = 0.33V