Using a table that lists standard heats of formation, you can calculate the change in enthalpy for a given chemical reaction. the change in enthalpy is equal to ∆hf0 of reactants minus ∆hf0 of products ∆hf0 of products plus ∆hf0 of reactants ∆hf0 of products divided by ∆hf0 of reactants ∆hf0 of products minus ∆hf0 of reactants

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The change in enthalpy for a given chemical reaction is equal to ∆hf0 of products minus ∆hf0 of reactants

The change in enthalpy allows chemists to know the energy that is consumed or produced in a chemical reaction.

If the change in enthalpy is negative (i.e. < 0) the reaction is exothermic, meaning that the reaction gives heat to the surroundings.

If the change in enthalpy is positive (i.e > 0) the reaction is endothermic, meaning that the reaction consumes heat from the surroundings.

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