Problem:
14.33 (a) The standard Gibbs free energy of formation of Tl3+(aq) is +215 kJ.mol-1 at 25°C. Calculate the standard potential of the Tl3+/Tl couple. (b) Will Tl+ disproportionate in aqueous solution?
In the book and in the solutions manual, the Standard Gibbs Free Energy of each half reaction is calculated and summed at the end to get the final reaction. Is there a reason why we can't just find the Standard Potential of each half reaction, sum those up, and then apply it to the Gibbs Free Energy equation (deltaG=-nFE). I did both and i got different answers. May someone explain. Thxxxx
14.33
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Re: 14.33
Postby melissa carey 1f » Mon Feb 19, 2018 3:05 pm
∆G is a state function, so you can add them. E_cell is NOT a state function, so you can't simply add them. This is why you have to convert to ∆G and back to E.
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