Is the change in enthalpy positive or negative for an exothermic reaction?

1 Answer
Dec 5, 2015



The change in enthalpy in an exothermic reaction is negative, since overall heat is lost ( "exo"thermic means that heat is leaving).

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Notice how the total enthalpy decreases in this exothermic reaction.

The opposite of this would be a positive change in enthalpy during an endothermic reaction.