Question

Identify the incorrect statements among the following:

• A. All enthalpies of fusion are positive.
• B. The magnitude of enthalpy change does not depend on the strength of the intermolecular interactions in the substance undergoing phase transformations.
• C. When a chemical reaction is reversed, the value of \( \Delta H^\circ \) is reversed in sign.
• D. The change in enthalpy is dependent on the path between initial state (reactants) and final state (products).

Hint:

Always remember that enthalpy is a state function, so its change depends only on the initial and final states, not the path.

Answer 1

The Correct Option is D

Statement (a) is true: All enthalpies of fusion are positive because energy is required to overcome intermolecular forces during fusion.
Statement (b) is false: The magnitude of enthalpy change indeed depends on the strength of intermolecular interactions, especially during phase transitions.
Statement (c) is true: When a chemical reaction is reversed, the sign of \( \Delta H^\circ \) is indeed reversed.
Statement (d) is false: Enthalpy change (\(\Delta H\)) is a state function, which means it only depends on the initial and final states, not the path taken. Thus, the change in enthalpy is not dependent on the path.