Use tabulated electrode potentials to calculate 𝛥𝐺rxn° for each reaction at 25 °C. c. Br2(l) + 2Cl–(aq) → 2 Br–(aq) + Cl2(g)

Verified step by step guidance

1. Identify the half-reactions involved in the given redox reaction. The oxidation half-reaction is: 2Cl^- \rightarrow Cl_2 + 2e^-. The reduction half-reaction is: Br_2 + 2e^- \rightarrow 2Br^-.
2. Look up the standard electrode potentials (E°) for each half-reaction from a table of standard reduction potentials. Note that the potential for the oxidation reaction will be the negative of the reduction potential for Cl_2.
3. Calculate the standard cell potential (E°_cell) for the reaction using the formula: E°_cell = E°_cathode - E°_anode.
4. Use the Nernst equation to relate the standard cell potential to the standard Gibbs free energy change: \Delta G°_{rxn} = -nFE°_{cell}, where n is the number of moles of electrons transferred (which is 2 in this case), and F is the Faraday constant (approximately 96485 C/mol).
5. Substitute the values for n, F, and E°_{cell} into the equation to calculate \Delta G°_{rxn}.

Key Concepts

Electrode Potentials

Electrode potentials, measured in volts, indicate the tendency of a chemical species to be reduced. Standard electrode potentials (E°) are measured under standard conditions and are crucial for predicting the direction of redox reactions. The more positive the electrode potential, the greater the species' ability to gain electrons and undergo reduction.

Gibbs Free Energy (ΔG)

Gibbs Free Energy (ΔG) is a thermodynamic quantity that indicates the spontaneity of a reaction. It combines enthalpy and entropy to determine whether a reaction can occur spontaneously at constant temperature and pressure. A negative ΔG value signifies a spontaneous reaction, while a positive value indicates non-spontaneity.

Nernst Equation

The Nernst Equation relates the electrode potential of a half-cell to the concentrations of the reactants and products involved in the redox reaction. It allows for the calculation of the cell potential under non-standard conditions, which is essential for determining the Gibbs Free Energy change (ΔG) for a reaction. The equation is given by E = E° - (RT/nF)ln(Q), where Q is the reaction quotient.