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Consider electrodes as electron pumps that try to maintain their equilibrium potential, according to their electrochemical state. When $\ce{Zn}$ and $\ce{Cu}$ electrodes (of e.g. the Daniell cell) are connected by external circuit, they mutually try to force their potential to each other, causing the current flowing across this circuit. The potential of $\ce{...


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The rate of electrolysis is the amount of copper $n\ce{(Cu})$ deposited at the cathode per second (in mol/s). This amount $n\ce{(Cu})$ is proportional to the time $t$ and to the current $I$ (in Amperes) according to the Faraday's law : $n = It/zF$. Now the current $I$ depends on the voltage $U$ according to Ohm's law : $I = U/R $ where $R$ is the resistance ...


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Let's take as an example a $1$ M $\ce{CuCl2}$ solution in water. If two platinum or charcoal electrodes are dipped into this solution, they will not react with this solution. If a small voltage (< $\pu{1.02 V}$} is applied on the electrodes, nothing happens. If now a higher continuous voltage (>$1.02$ V) is applied, electrolysis proceeds. At the ...


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In hopes of helping others that have the same question, I think a have a partial answer. From https://www.sciencedirect.com/science/article/pii/B9780124095472111497 "Traditionally, electrochemical double-layer theory has been concerned with the so-called ideally polarizable interfaces, at which by definition no electrochemical reaction takes place and ...


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Copper ion concentration is a variable, of course. However, the rate of copper deposition is DIRECTLY related to the current being passed. Well, except for the possible complexities addressed below. If increasing the copper ion concentration increases the rate of copper deposition, it is likely because the power supply is not regulated. The resistance of the ...


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There are electrode reactions controlled by electron transfer(slow ones) or by diffusion(fast ones). Depending on choice of forced electrode potentials, electrolyzer geometry and ion concentration, many reactions can be arranged to be electron-transfer limited or diffusion limited. If the cathode potential is decreased below its equilibrium potential, the ...


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Since AC can be capacitively coupled to the solution, metallic electrodes don't need to contact the solution -- they can be outside an insulating container, e.g., glass or PTFE, avoiding introducing metal ions. At moderate AC frequencies, ions won't migrate an appreciable distance in one direction before returning to that position on the opposite half of ...


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@MatNX, as you state, "sensitive technology and high temperatures are typically a very bad match." However, there is no magic way to "make" cold, only to move heat from one location to another. Presumably, since you state you have an engineering background, you're familiar with the laws of thermodynamics. Any heat you remove from an IC ...


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Thermodynamically if you calculate the equilibrium constant the equilibrium quotient depends on number of moles of both reactants as well the number of moles of products that is reaction concentration at the equilibrium.more the free energy of reactants the reaction will proceed in a spontaneous manner the more feasible the reaction . Likewise the more the ...


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Anions travel away from a cathode just partially, until there is built the counter potential gradient due charge displacement. When both gradients cancel each other, the migration stops. That happens when there is no ongoing electrolysis, e.g. if too small external voltage is applied. When there is ongoing electrolysis, the balance is continuously disturbed, ...


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OK, some details, on this galvanic cell construction where, this reference cites the following step, to quote: Tightly wrap a piece of copper wire five times around a galvanized nail just under the head of the nail. So, as "galvanized" means Zinc coated, iron is not actually (at least at the start) part of this galvanic cell. As such, without ...


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Instead of halides, consider hydroxides A eutectic of sodium hand potassium hydroxides melts at 170°C. See: Sergei Devyatkin. "Interaction of Oxides and Molten Alkalis, Products of Reaction and Application", Sustainable Industrial Processing Summit & Exhibition, Volume 7: Ionic Liquids & Energy Production, Edited by Florian Kongoli, Flogen, ...


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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 ...


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The answer is yes, you will get a potential difference of 0.2-(-2.37) = 2.57 V, if Mg and carbon filament are used as the electrode materials and connected into one circuit. The third digit after the decimal is removed, because different resources give slightly different values. From our own experiments using glassy carbon, its open circuit potential is -0....


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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 ...


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