The change in enthalpy is a measure of the heat reaction at:
Correct answer: D. Constant pressure
- A. Constant Volume
- B. Constant Pressure and volume
- C. Variable pressure
- D. Constant pressure
Explanation
Enthalpy is a thermodynamic state function that represents the internal energy of a system plus the product of pressure and volume. It is expressed as ΔH, which is the change in enthalpy during a chemical reaction. Constant pressure: At constant pressure, the change in enthalpy is equal to the heat absorbed or released by the system, as well as the work done by or on the system against the constant pressure.
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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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