# Homework Help: Cell Potential with Nernst Equation

1. Feb 5, 2014

### davev

1. The problem statement, all variables and given/known data

2. Relevant equations
Nernst Equation where Q = [product]/[reactants], R = 8.314, F = 96500

3. The attempt at a solution
I got E° to be 0.012 V because E° of cathode - E° of anode. -0.131 - (-0.143) = 0.012.

The balanced equation I got was: Pb2+ + Sn → Pb + Sn2+

For the values of Q, I added 0.349 M to the concentration of Sn2+ as it's the product, and I subtracted 0.349 M from the concentration of Pb2+ as it's the reactant.

Plugging everything into the equation:
E = 0.012 V - ((8.314 * 271)/(2 * 96500)) * ln(1.318/0.576) = 0.0023 V. This answer is wrong, but I cannot figure out what I'm doing wrong here. Please help!

Last edited: Feb 5, 2014
2. Feb 5, 2014

### Staff: Mentor

I can't find anything wrong.

Not that I am infallible, but there are two of us stumped now.

3. Feb 5, 2014

### davev

The answer I put in is what the system shows as the correct answer now that the homework has closed. I don't understand why it was marked incorrect, but I'll just have to email my professor.