The following balanced reactions occur under standard conditions (298 K, 1 atm).
Reaction I: 2 KClO₃(s) → 2 KCl(s) + 3 O₂(g)
Reaction II: N₂(g) + 3 H₂(g) → 2 NH₃(g)
Reaction III: C₆H₁₂O₆(s) → 2 C₂H₅OH(l) + 2 CO₂(g)
(a) For each reaction, predict the sign (positive, negative, or approximately zero) of the standard entropy change, ΔS°, and justify your prediction in terms of both phase changes and the change in the total number of moles of species present.
(b) Rank the three reactions from the one expected to have the most positive ΔS° to the one expected to have the most negative ΔS°. Provide a concise explanation for your ranking that refers explicitly to the reasoning developed in part (a).
(a) Predict and justify the sign of ΔS° for Reaction I.
(a) Predict and justify the sign of ΔS° for Reaction II.
(a) Predict and justify the sign of ΔS° for Reaction III.
(b) Rank Reactions I–III from largest positive to most negative ΔS°, with justification.