Question:
Enthalpy change is always negative for which one of the following processes?
Enthalpy change is always negative for which one of the following processes?
Updated On: Apr 4, 2025
- Enthalpy of ionisation
- Enthalpy of sublimation
- Enthalpy of vapourisation
Enthalpy of combustion
Enthalpy of fusion
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The Correct Option is D
Solution and Explanation
The enthalpy of combustion is the heat change when one mole of a substance is completely burnt in excess oxygen under standard conditions.
This is an exothermic process, which means it releases heat to the surroundings.
Therefore, the enthalpy change (\( \Delta H \)) is always negative for combustion.
Correct Answer:
Enthalpy of combustion
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