Which one of the following enthalpy changes is always exothermic in nature?
Correct answer: A. Enthalpy of combustion
- A. Enthalpy of combustion
- B. Enthalpy of solution.
- C. Enthalpy of formation
- D. Enthalpy of atomization
Explanation
Combustion reactions release heat, so the enthalpy change of the system, H, will always be negative.
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About Enthalpy
Enthalpy is the heat content of a system measured at constant pressure, and its change indicates whether a reaction or physical process is endothermic or exothermic. The topic covers state functions, enthalpy diagrams, standard enthalpy of formation, combustion and neutralisation, and the relationship between ΔH and internal energy change.
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