You are given the following three half-reactions:(1) Fe³⁺(aq) + e⁻ ⇄ Fe²⁺(aq) (2) Fe²⁺(aq) +2e⁻ ⇄ Fe(s) (3) Fe³⁺(aq) +3e⁻ ⇄ Fe(s) (d) Calculate E°half-cell for (3) from its ΔG°.

Respuesta :

a) ΔG° for (1) = -7.4 × 10⁴ J

ΔG° for (2) = 8.5 × 10⁴ J

The relation between ΔG° and E° is

                     ΔG°= - nFE°     Farad(F ) = 96500 Coulomb

                      1C × Volt = 1 Joule

For (1) reaction, Fe³⁺ (aq) + e⁻ ⇄ Fe²⁺(aq)  ,  n = 1

        (ΔG°)₁ = - nFE°

                   = -1 × 96500×0.77 J

                   = - 74.305 J = -7.4×10⁴ J

For (2) reaction, Fe²⁺ (aq) + 2e⁻ ⇄ Fe (s),  n = 2

       (ΔG)₂  = -2× 96500 × (-0.44V)

                  = 84,920 J = 8.5 × 10⁴ J

b) For (3) reaction, Fe³⁺ (aq) + 3e⁻ ⇄ Fe(s)

    (ΔG°)₃  =  (ΔG°)₁  +  (ΔG°)₂

                =   -7.4 × 10⁴J + 8.5 × 10⁴ J

                =   1.1 × 10⁴ J

c)     Fe³⁺ (aq) + 3e⁻ ⇄ Fe(s)  ,  n = 3

      (ΔG°)₃  =  (ΔG°)₁  +  (ΔG°)₂

      - 3FE°  =   - F × 0.77 V + 2 F ( 0.44 V )

          3 E°  =     0.77 V - 0.88 V

              E°  =      -0.037 V

Learn more about Faradays Law at https://brainly.com/question/14012383

# SPJ4

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Question:  You are given the following three half- reactions:

        1)  Fe³⁺ (aq) + e⁻ ⇄ Fe²⁺(aq)                      E° = + 0.77 V

        2)  Fe²⁺ (aq) + 2e⁻ ⇄ Fe (s)                       E° = - 0.44 V

        3)  Fe³⁺ (aq) + 3e⁻ ⇄ Fe(s)

a) Calculate ΔG° for (1) and (2) from their E° values

b)  Calculate ΔG° for (3) from (1) and (2)

c)  Calculate E° for (3) from its ΔG°