# Homework Help: How do I determine anode/cathode?

1. Mar 31, 2016

### weirdobomb

1. The problem statement, all variables and given/known data
The solubility product for CuI(s) is 1.1 x 10^-12. Calculate
the value of cell potential for the half-reaction

CuI + e- => Cu + I-

I find the other half reaction is Cu+ + e- => Cu E=0.52V

2. Relevant equations
I use the Nernst equation to solve for the standard cell potential, then fill in E = E(cathode) - E(anode) to solve the remaining unknown.

3. The attempt at a solution
Heads up I found the solution to be 0.18675 Volts through trial and error, the solutions at the back of the textbook say 0.19V. I had a hard time reasoning which is the anode/cathode. How do I find this? Is it beacuse when solving for the standard cell potential in the Nernst equation that I get E = -0.707V?

Also, I'm not sure if this is an electrolytic cell or galvanic cell but does that matter when solving?

2. Mar 31, 2016

### weirdobomb

I think I have solved my question, I was over thinking it. The half-reaction is given as it is and by looking at it's form, it is the cathode. Thus Cu+ + e- => Cu is the anode.