Calculate the cell potential E at 25°C for the reaction 2 Al(s) + 3 Fe²⁺(aq) → 2 Al³⁺(aq) + 3 Fe(s)
Given that [Fe²⁺] = 0.020 M,[Al³⁺] = 0.10 M,and the standard reduction potential is -1.66 V for Al³⁺/Al and -0.45 V for Fe²⁺/Fe.

Question

Quizplus · Accepted Answer

We can use the Nernst equation to calculate the cell potential: E = E° - (RT/nF) * ln(Q) where E° is the standard cell potential, R is the gas constant, T is the temperature in Kelvin, n is the number of electrons transferred in the reaction, F is Faraday's constant, and Q is the reaction quotient. First, we need to determine the value of Q. The reaction quotient for this reaction can be written as: Q = ([Al³⁺]^2/[Fe²⁺]^3) Substituting the given concentrations: Q = (0.1^2/0.02^3) = 125 Next, we can calculate the cell potential: E = -1.66 V - (0.02569 V/K) * ln(125) E = +1.18 V Therefore, the best choice is C.

Calculate the Cell Potential E at 25°C for the Reaction