Match the columns — Thermodynamics and Thermochemistry Chemistry Question

💡 Solution & Explanation

(A) Standard state element, formation properties are exactly zero. (B) $1.5\text{O}_2 \to \text{O}_3$: endothermic ($\Delta H > 0$) with decrease in moles ($\Delta S < 0$). (C) $\text{I}_2\text{(s)} \to \text{I}_2\text{(g)}$: endothermic phase change ($\Delta H > 0$) with increase in disorder ($\Delta S > 0$). (D) $\text{C(s)} + 0.5\text{O}_2\text{(g)} \to \text{CO(g)}$: exothermic ($\Delta H < 0$) with net production of gaseous moles ($\Delta S > 0$).