The change in heat energy in a chemical reaction at constant temperature and pressure is called:
Correct answer: A. Enthalpy change
- A. Enthalpy change
- B. Heat of sublimation
- C. Internal energy change
- D. Heat of formation
Explanation
The change in heat energy in a chemical reaction at constant temperature and pressure is called enthalpy change. The enthalpy of sublimation, or heat of sublimation, is the heat required to change one mole of a substance from solid-state to a gaseous state at a given combination of temperature and pressure. The change in the internal energy of a system is the sum of the heat transferred and the work done. Heat of formation of a compound is the change of enthalpy during the formation of 1 mole of the substance from its constituent elements
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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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