Standard Reduction Potentials Sn*(aq) + 2e → Sn²*(s) E° = 0.15 V K"(aq) + le → K(s) E° = -2.92 V |3D Faraday's constant is 96,485 C/mole e's An electric current of 1.00 ampere is passed through an aqueous solution of Ni(NO3)2. How long will it take to plate out exactly 1.00 mol of nickel metal, assuming 100 percent current efficiency? A. 386,000 s B. 193,000 s C. 96,500 s D. 48,200 s

7. Please answer the following questions. (a) Given the following reduction potentials Cd (OH)2 (s) + 2e → Cd (s) + 2 OH (aq) Eºred = -0.76 V NIO(OH) (s) + H₂O (1) + e → Ni(OH)2 (aq) + OH (aq) Eºred = +0.49 V Calculate the standard emf of the nickel-cadmium (nicad) rechargeable battery. *hint: the reaction for the discharge of nicad battery is: Cd (s) + 2 NIO(OH) (s) + 2 H₂O (1)→ 2Ni(OH)2 (aq) + Cd(OH)2 (s) (b) A typical nicad voltaic cell generates an emf of +1.30 V. Why is there a difference between this value and the one you calculated in part (b)? (c) Calculate the equilibrium constant for the overall nicad reaction based on this typical emf value.

Given the following2AgCl(s) +X(s) → 2Ag(s) + 2Cl-(aq) + X2+(aq)         E°cell = 0.73 V and AgCl(s) → Ag(s) + Cl-(aq)          E°= 0.222 V What is the standard reduction potential for X2+(aq)?

Calculate the equilibrium constant, K, for the reaction shown at 25 °C. Fe+(aq)+B(s) + 6 H, O(1) → Fe(s) + H,BO,(s) + 3 H,O*(aq) The balanced reduction half-reactions for the equation and their respective standard reduction potential values (E") are Fe3+ (aq) + 3 e- → Fe(s) H,BO, (s) + 3 H,0*(aq) + 3 e- – B(s) + 6 H, O(1) E' = -0.04 V E' = -0.8698 V K =