What is the standard reduction potential E o for F e 3 + → F e ? Given that: F e 2 + + 2 e - → F e ; E F e 2 + / F e o = - 0.47 V F e 3 + + e - → F e 2 + ; E F e 3 + / F e 2 + o = + 0.77 V

Step-by-step solution

​(i) F e 3 + → F e E 1 o ; 'n' factor = 3 Δ G 1 = − 3 × F × E 1 o (ii) F e 3 + + e − → F e 2 + E 2 o ;0.77 'n' factor = 1 Δ G 2 = − 1 × 0.77 × f (iii) F e 2 + + 2 e − → F e E 3 o ;0.77 'n' factor = 2 Δ G 3 = 0.47 × 2 × f Δ G 1 = Δ G 2 + Δ G 3 − 3 f E 1 o = − 1 × 0.77 × f + 2 × 0.47 × f E 1 o = − 2 × 0.47 + 0.77 3 = − 0.057 V