Which of the following specific chemical reactions are characteristically endothermic processes () a — Thermodynamics and Thermochemistry Chemistry Question

💡 Solution & Explanation

The direct synthesis of nitric oxide ($NO$) from elemental nitrogen and oxygen is a notable exception in formation reactions and is highly endothermic. The cleavage or dissociation of any stable chemical bond (such as $H-Cl$) always requires an input of bond dissociation energy, making it an endothermic process. Conversely, the combustion of carbon and the Haber synthesis of ammonia are strongly exothermic.