## Final Exam 2014 - Q3A

Alexis Elliott 1J
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Joined: Wed Sep 21, 2016 2:59 pm

### Final Exam 2014 - Q3A

For this question we have to choose from a list of elements that we should use for a galvanic cell. I am confused as to how we would choose the correct elements and why 5 were chosen. I would think that max you would need 3.

Thank you!

Chem_Mod
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### Re: Final Exam 2014 - Q3A

You would be given a list of reduction potentials for all of the components and would need to compare the voltage of the total cell for the different possible combinations to find the one that gives the highest cell potential/voltage. For this example the Zn(s) and $Zn(NO_3)_2$ would be your anode source and then using the two aqueous Fe solutions you would then need a metal electrode which is where the Pt(s) comes in. Generally speaking you would likely need at least 4 things (2 compounds for your anode and 2 compounds for the cathode).

Vincent Tse 2B
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### Re: Final Exam 2014 - Q3A

You would want to choose elements that will give you the highest possible voltage by looking at their corresponding half-reactions.

I found this post to be very helpful: viewtopic.php?t=5476

Hope it clarifies things!