Above what temperature does the following reaction become nonspontaneous? FeO(s)+ CO(g)→ CO₂(g)+ Fe(s)ΔH = -11.0 kJ; ΔS = -17.4 J/K

Question

Quizplus · Accepted Answer

For a reaction to be spontaneous, the Gibbs free energy change (ΔG) must be negative. The equation ΔG = ΔH - TΔS can be rearranged to solve for the temperature (T) at which ΔG = 0 (the threshold between spontaneity and non-spontaneity): T = ΔH/ΔS. Plugging in the values (ΔH = -11.0 kJ = -11000 J; ΔS = -17.4 J/K), we get T = -11000 J / -17.4 J/K = 632 K. Above this temperature, the reaction becomes nonspontaneous because the positive TΔS term outweighs the negative ΔH, making ΔG positive.

Above What Temperature Does the Following Reaction Become Nonspontaneous? FeO(s)