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Nernst Equation Help

For my A2 Chemistry coursework I am looking at determining the copper concentration in brass. A method by which I was going to test this was by setting up two half-cells and connecting them by a salt bridge and putting a high resistance voltmeter between them. The issue I have is that I don't know how to work out the concentration using this method or the Nernst equation. I'm not sure whether I need to test using known concentrations of zinc and copper (my anode and cathode) and plot a graph, or just do one test and I can calculate from there. And if I do plot a graph, how could I read off it the concentration?
Thanks for any help!

Reply 1

username1445490

Why are you using this method. I can't it yielding good results easily.
Have you thought of iodometric determination?
See http://www.csudh.edu/oliver/che230/labmanual/copbrass.htm
This technique would also work on brass as well as copper coins. http://www.creative-chemistry.org.uk/alevel/module5/documents/N-ch5-17.pdf

Reply 2

ThePhoenixLament

Original post by Madasahatter

I am using both those methods as well, I just wanted something a little more complex and interesting. I wasn't anticipating it being useful but it means I can explain limitations and say I have gone beyond the scope of the course.
Thanks for the links- they've got easier and more precise methods than the ones I had used!