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A zinc rod is being placed in a solution containing 0.1 M of copper (II) ions. Calculate the corrosion potential of the zinc rod in a galvanic couple with a standard hydrogen electrode at 25°C.

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To calculate the corrosion potential of the zinc rod in a galvanic couple with a standard hydrogen electrode, we need to consider the half-cell reactions and the Nernst equation.The half-cell reactions are:Zn s   Zn aq  + 2e  E = -0.76 V Cu aq  + 2e  Cu s   E = +0.34 V The overall reaction is:Zn s  + Cu aq   Zn aq  + Cu s The cell potential  E_cell  is the difference between the reduction potential of the cathode  copper  and the anode  zinc :E_cell = E Cu/Cu  - E Zn/Zn  = 0.34 V -  -0.76 V  = 1.10 VNow we need to apply the Nernst equation to account for the non-standard conditions  0.1 M Cu :E = E -  RT/nF  * ln Q Where:E = corrosion potentialE = standard cell potentialR = gas constant  8.314 J/molK T = temperature in Kelvin  25C = 298 K n = number of electrons transferred  2 for this reaction F = Faraday's constant  96485 C/mol Q = reaction quotient = [Zn]/[Cu]Since the zinc rod is being placed in the solution, we can assume that [Zn] is negligible compared to [Cu]. Therefore, Q  1/[Cu] = 1/0.1 = 10.Now we can plug in the values:E = 1.10 V -  8.314 J/molK * 298 K /  2 * 96485 C/mol   * ln 10 E = 1.10 V -  0.0257 V  * ln 10 E = 1.10 V - 0.0592 VE  1.04 VThe corrosion potential of the zinc rod in a galvanic couple with a standard hydrogen electrode at 25C is approximately 1.04 V.

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