Which of the following is/are endothermic compound(s)? — Thermodynamics and Thermochemistry Chemistry Question

💡 Solution & Explanation

Endothermic compounds possess a positive standard enthalpy of formation ($\Delta H_f^\circ > 0$). Nitric oxide (NO) is formed endothermically. $\text{CO}_2$, CO, and $\text{NH}_3$ are formed exothermically ($\Delta H_f^\circ < 0$).