QUESTION 6.8 The electrochemical cell represented in the accompanying diagram consists of two electrodes. One is a solid NiO/Ni mixture. The other is a gaseous 0, electrode. The porous platinum coating acts only as a catalyst. Porous platinum NIONI ZrO2 +Y_03 (solid solution) 02 The electrolyte is a ZrO/Y.O, solid solution that conducts oxygen ions (0) between the oxygen side and the NO/Ni side. (a) Calculate the equilibrium oxygen partial pressure at the NiO/Ni electrode (2Ni + 0,2NiO) at 1000 K. (b) Identify the cathode and the anode in this electrochemical cell and write the half-cell reactions for the two electrodes. (Specify the direction of the reaction.) (c) What is the open circuit voltage at 1000 K when the pressure of oxygen on the oxygen electrode side is one atmosphere? (d) What is the open circuit voltage at 1000 K when the oxygen pressure on the oxygen electrode side is 10 atm? DATA For Ni + $0.- NO AG = -244.550 + 98.5 T where AG, is in joules and T is in kelvin