Question

These equations below show two standard reduction potentials. Fe3+(aq) + e– Fe2+(aq) Eo = +0.77 Cu2+(aq) + 2e– Cu(s) Eo = +0.34 Which value represents the standard cell potential of the spontaneous overall reaction? Use E cell = E red, cathode – E red, anode. –1.11 V –0.43 V +0.43 V +1.11 V

Answer 1

Answer:

= +0.43 V

Explanation:

The two standard reduction potentials are;

Fe³⁺(aq) + e⁻ → Fe²⁺(aq) E₀ = +0.77 V

Cu²⁺(aq) + 2e⁻ → Cu(s)    E₀ = +0.34 V

The overall reaction is;

Fe³⁺(aq) + Cu(s) → Fe²⁺(aq) + Cu²⁺(aq)

To calculate the standard cell potential of the overall reaction, we use the equation;

Ecell = E redu, cathode - E red, anode

From the reaction; Copper lost electrons to form copper ions (Cu²⁺) (Oxidation) while Fe³⁺ gained electrons to form Fe²⁺ (reduction)

Therefore;

E cell = + 0.77 v - (+0.34 v)

        = + 0.43 V

Hence, the standard cell potential of the overall reaction is +0.43 V