A voltaic cell utilizes the following reaction and operates at 298 K:
3Ce4+(aq)+Cr(s)→3Ce3+(aq)+Cr3+(aq).
What is the emf of this cell when [Ce4+]= 2.5 M, [Ce3+]= 1.9×10-2 M , and [Cr3+]= 1.1×10-2 M?
What is the emf of this cell when [Ce4+]= .39 M, [Ce3+]= .77 M, and [Cr3+]= 1.3 M ?