Calculate ΔG° (in kJ) for a reaction where ΔH°= +63 kJ, ΔS°= +675 J/K, and T = 298 K. Use the formula ΔG° = ΔH° - TΔS°.

Calculate the standard free-energy change (ΔG°) at 25 °C for the reaction: Mg(s) + Fe²⁺(aq) → Mg²⁺(aq) + Fe(s). Given: E°(Mg²⁺/Mg) = -2.37 V and E°(Fe²⁺/Fe) = -0.44 V.

Calculate ΔG° (in kJ) for a reaction where ΔH° = -87 kJ, ΔS° = -223 J/K, and T = 298 K.

Calculate ΔG°rxn for the reaction: CaCO3(s) --> CaO(s) + CO2(g). Use the following reaction and given ΔG°rxn value: Ca(s) + CO2(g) + 1/2 O2(g) --> CaCO3(s) ΔG°rxn = -734.4 kJ. Assume ΔG°f for CaO(s) is -604.0 kJ/mol and ΔG°f for CO2(g) is -394.4 kJ/mol.

Consider the following reaction: CO2(g) + CCl4(g) ⇌ 2COCl2(g). Calculate ΔG for this reaction at 25 °C under these conditions: PCO2 = 0.140 atm, PCCl4 = 0.185 atm, PCOCl2 = 0.755 atm. Given that ΔG°f for CO2(g) is −394.4 kJ/mol, what is the value of ΔG?

Consider the following reaction: C2H4(g) + H2(g) → C2H6(g) with ΔH = -137.5 kJ and ΔS = -120.5 J/K. Calculate ΔG at 25 °C and determine whether the reaction is spontaneous.