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I am wonder if the direction the electron flow in a voltaic cabinet be reversed such that the cathode becomes the anode and vice versa. I understand this is not possible for two traditional half-cells, but what about non-standard half-cells at STP ?
deserve to going to non-standard conditions reverse the cell potential that a voltaic cell?
I have already answered the question, in the affirmative, because that a simple tin and also lead galvanic cell, here: https://moment-g.com/a/116734/79678.
What complies with is an elaboration through some specific values and also illustrative figures. In fig. 1, the tin and also lead voltaic cell is shown:
In fig. 1, the tin and lead ion concentrations are each precisely $pu1 M$ and also the cabinet potential is $pu+0.014 V$, with tin together the anode. All important equations are shown in the figure and the normal simplifying presumptions are made: unity activity coefficients, zero cell resistance, etc. The electron flow is indigenous $ceSn$ come $cePb$.
In the following figure, the command ion concentration is $pu0.3363 M$ if the believe ion concentration stays at exactly $pu1 M$. This results in zero cell potential, as shown in fig. 2:
Since the cabinet potential is zero, the is a moot suggest to contact tin the anode: the cell is no doing (net) electromoment-g.com. There is no net electron flow.
In the last figure, the lead ion concentration is precisely $pu0.1 M$ if the believe ion concentration remains at exactly $pu1 M$. This results in a cell potential of $pu+0.016 V$, as shown in the figure:
But currently lead is the anode and also tin is the cathode. The electron flow is indigenous $cePb$ to $ceSn$.
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So an altering the ion concentration to non-standard values deserve to reverse the electron flow direction. However this was particularly easy case due to the fact that the two metal electrodes had standard potentials the were relatively close. Because that the Daniell cell, through $ceZn$ and also $ceCu$, it would certainly not be feasible.