How does the Standard Cell potential of the Nernst equation work? [closed]








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$$
E = E^\circ - \dfrac{RT}{nF} \ln Q
$$
For calculations, the standard cell potential is typically given with a reference page, using elements at standard conditions. While doing an experiment with varied concentrations of one of the electrodes, there will be an effect on the voltage due to the reaction quotient from this equation.


But, would you also have to account for a change in the standard cell potential of that electrode due to concentration, or is that value kept at the same standard condition cell potential?


For instance, the copper-zinc reaction is around $\pu{1.1 V}$ but if you conducted an experiment with copper at $\pu{0.0 1M}$ instead, would you still use the value of $\pu{1.1 V}$?


How about with an experiment of varying temperatures?


If experimenting with a system at $\pu{50 ^\circ C}$, would you need to use a standard potential with respect to the elements at this new temperature of $\pu{50 ^\circ C}$, or do you still use the standard potentials of $\pu{25 ^\circ C}$?


Effectively just wondering if the $E^\circ$ value for this equation is dependent on solely the elements and to look at their data values for STP or do you have to take into account the elements and their conditions to form an $E^\circ$ value.




If the concentration $\ce{[Cu^{2+}]}$ is $0.01 M$, the potential of the copper electrode becomes $\pu{E\_{Cu/Cu^{2+}} = 0.34 V - 2· 0.0295 V = 0.28 V}$. If this copper electrode is coupled with a zinc electrode where $\ce{[Zn^{2+}] = 1 M}$, the potential of the cell becomes $\pu{0.76 V + 0.28 V = 1.04 V}$


Now the effect of temperature change can be calculated from the formula $2.30\frac{RT}{zF}$. At $25°C$, this factor is $0.059/z$. At $50°C$, it becomes $0.0636/z$


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Okay, so I want to provide another answer just to elaborate on what was said.
$\ce{E^\circ}$ refers to the cell potential at standard conditions (By the way, it is not STP. STP is for gases primarily). So if we were doing an experiment at 50°C instead of 25°C, then we would use the Nernst to find the cell potential at the specific temperature (E). The standard cell potential ($\ce{E^\circ}$) value for something will always be the same.


Again standard conditions are $\pu{1M}$ of solutions, 1 atm of pressure, and 25°C.


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