Final answer:
The value of the standard electrode potential (E°) for a redox reaction with a ΔG° of +18.55 kJ and 3 transferred electrons at 25°C can be calculated using the equation E° = -ΔG°/nF.
Step-by-step explanation:
The student is asking for the value of the standard electrode potential (E°) given the standard free energy change (ΔG°) of a reaction at 25°C is +18.55 kJ, where 3 electrons are transferred. To find E°, we can use the equation ΔG° = -nFE°, where 'n' is the number of moles of electrons transferred, 'F' is Faraday's constant approximately equal to 96,485 C/mol e⁻, and E° is the standard electrode potential we need to find.
First, let's convert the given ΔG° to joules as we need to match the units with Faraday's constant: 18.55 kJ = 18,550 J. Then, we can rearrange the equation to solve for E°: E° = -ΔG° / (nF). Plugging in the values, we get E° = -18,550 J / (3 * 96,485 C/mol e⁻), which gives us the standard electrode potential E°.
It's important to note that the value of E° found by just adding potentials may differ significantly from the correct value, and the sign is also crucial as it indicates the spontaneity of the redox reaction.