Interpretation:
The reason for change in the sign of
Concept introduction:
Enthalpy of a solution is the change in energy when one mole of the substance is dissolves in a specified amount of solvent at a constant temperature and pressure.

Answer to Problem 98A
The sign of enthalpies is change because positive sign is used for enthalpy absorbed and negative sign for enthalpies released.
Explanation of Solution
Enthalpy of a solution is the change in energy when one mole of a substance is dissolved in a specified amount of solvent at a constant temperature and pressure. When a thermo chemical equation is reveres then the sign of enthalpies is changed because positive sign is used for enthalpy absorbed and negative sign for enthalpies released.
The sign is changed because positive sign is used for enthalpy absorbed and negative sign for enthalpies released.
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Chemistry: Matter and Change
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