(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Line Notation Fe | Fe^(2+) (0.587) || Cd^(2+) (1.009) | Cd

T = 297 K

E(cell standard) = .04 V

Find the potential when [Fe^(2+) changes by .393 M

Work

Cd^(2+) + Fe --> Cd + Fe^(2+)

Q = [Fe^(2+)] / [Cd^2+]

Q= [.587 + .393] / [1.009-.393]

3. The attempt at a solution

After I got the problem wrong and I worked backwards to get the answer but I am not sure I understand it. When finding the Q value, how do I know to add .393 M to Fe^2+ and subtract .393 M from Cd^(2+)? To me the question is vague and just says changes by .393 M, not increase or decrease so how I know [Fe^2+] must increase?

Thanks

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# Homework Help: Electrochemistry - Cell Potential

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