Calculate the potential for each cell as shown below and indicate whether the me

Question

Calculate the potential for each cell as shown below and indicate whether the metal electrode in the half-reaction opposite the standard hydrogen electrode, S H.E., would be the anode or the cathode if the cell was shorted and electrons were allowed to flow freely at 25 degree C. A) S.H.E.|| Zn^2+(aq, 0.0570 M)|Zn(s) E^o_Zn^2+/Zn = -0.762 V The Zn electrode is the anode. cathode. B) Pt(s)|V^3+(aq, 0.275 M), V^2+(aq, 0.00380 M)||S.H.E. E^o_V^3+/V^2+ = -0.255 V The Pt electrode is the anode cathode

Explanation / Answer

B. The half cell reaction is V3+ (0.275M ) ----> V2+(0.00380M)

Equilibrium constant , K = [V2+]/[V3+]

= 0.00380 / 0.275

= 0.0138

According to Nernst Equation ,

E = Eo - (0.059 / n) log K

   = Eo - (0.059 / n) log K

Where

E = electrode potential of the cell = ?

Eo = standard electrode potential = +0.255 V

n = number of electrons involved in the reaction = 1

Plug the values we get

E = Eo - (0.059 / n) xlog K

   = +0.255 - (0.059 / 1 ) x log 0.0138

= +0.3647

Related Questions

Navigate

• Browse (All)
• Browse C
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.