Answer:
Negative
Explanation:
Enthalpy changes are heat changes accompanying physical and chemical changes. An enthalpy change is the difference between the sum of the heat contents of products and sum of the heat contents of reactants.
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In exothermic change, heat is liberated to the surrounding. The surrounding becomes hotter at the end of the changes.
Enthalpy change is assigned a negative sign as the sum heat contents of products is less than that of the reactants.