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Calculate the exchange current density at the interface between a silver electrode and an aqueous solution of silver ions, given that the standard reduction potential for the Ag+/Ag half-cell is +0.80 V, the concentration of Ag+ in the solution is 0.025 M, and the temperature is 25°C.

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To calculate the exchange current density  i  at the interface between a silver electrode and an aqueous solution of silver ions, we can use the Butler-Volmer equation:i = n * F * k *  C_red * C_ox ^0.5where:- n is the number of electrons transferred in the redox reaction  for Ag+/Ag, n = 1 - F is the Faraday constant  96485 C/mol - k is the standard rate constant- C_red is the concentration of the reduced species  Ag, which is in solid form, so we assume it to be 1 - C_ox is the concentration of the oxidized species  Ag+, 0.025 M To find k, we can use the Nernst equation:E = E -  RT/nF  * ln Q where:- E is the reduction potential at the given conditions- E is the standard reduction potential  +0.80 V for Ag+/Ag - R is the gas constant  8.314 J/molK - T is the temperature in Kelvin  25C = 298.15 K - Q is the reaction quotient  C_red/C_ox Since the reaction is at equilibrium, E = 0 V. Therefore, we can solve for Q:0 = 0.80 -  8.314 * 298.15 / 96485  * ln Q ln Q  = 0.80 * 96485 /  8.314 * 298.15 Q = exp 0.80 * 96485 /  8.314 * 298.15  Q  1.69 * 10^6Now, we can find the concentration of Ag:C_red = Q * C_oxC_red = 1.69 * 10^6 * 0.025C_red  4.23 * 10^4Since Ag is in solid form, we assume C_red to be 1.Now, we can use the Tafel equation to find k:E = E -  RT/nF  * ln k 0.80 = 0 -  8.314 * 298.15 / 96485  * ln k ln k  = 0.80 * 96485 /  8.314 * 298.15 k = exp 0.80 * 96485 /  8.314 * 298.15  k  1.69 * 10^6Finally, we can calculate the exchange current density:i = n * F * k *  C_red * C_ox ^0.5i = 1 * 96485 * 1.69 * 10^6 *  1 * 0.025 ^0.5i  1.63 * 10^11 A/mThe exchange current density at the interface between a silver electrode and an aqueous solution of silver ions is approximately 1.63 * 10^11 A/m.

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