If the value of E°_cell is 2.10 V for the reaction
F₂ (g) + 2Fe²⁺ (aq) → 2Fe³⁺ (aq) + 2F^- (aq) ,
What is the value of E°_cell for
F^- (aq) + Fe³⁺ (aq) → Fe²⁺(aq) + 1/2 F₂(g) ?

Question

If the value of E°_cell is 2.10 V for the reaction F₂ (g)+ 2Fe²⁺ (aq)→ 2Fe³⁺ (aq)+ 2F^- (aq), What is the value of E°_cell for F^- (aq)+ Fe³⁺ (aq)→ Fe²⁺(aq)+ 1/2 F₂(g)?

Quizplus · Accepted Answer

The second reaction is the reverse of the first one, but with half the amount of F2 gas involved. Reversing a reaction changes the sign of E°cell, and halving the reaction changes the magnitude. However, the magnitude remains the same in this case because the potential is an intensive property, not dependent on the amount of substance. Therefore, the correct answer is -2.10 V.

If the Value of E°cell Is 2

If the Value of E°_cell Is 2