## Cell Diagrams

$\Delta G^{\circ} = -nFE_{cell}^{\circ}$

JuliaPark2H
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Joined: Fri Sep 25, 2015 3:00 am

### Cell Diagrams

Some cell diagrams have more than just a solid metal electrode and an aqueous ion form on either side of the salt bridge double line. When is this the case and is there a good guide to follow when writing cell diagrams?

Chem_Mod
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### Re: Cell Diagrams

You have just a solid electrode in aqueous solution if the material the electrode is made of is produced or used up by the oxidation or reduction reactions. Also, the metal produced or used up needs to conductive. We need to use an inert metal electrode when ions are not oxidized/reduced to become an uncharged conducting metal (e.g. Fe3+ becomes Fe+ in the cathode, requiring a platinum electrode).