Reaction Enthalpy (Hess's Law)
PROCalculate standard enthalpy of reaction ΔH°rxn from bond enthalpies or heats of formation.
PhD Chemistry (Analytical), MRSC
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About the Reaction Enthalpy (Hess's Law)
Hess's Law states that the total enthalpy change for a reaction is independent of the pathway. ΔH°rxn = ΣΔHf°(products) − ΣΔHf°(reactants).
How it works
\Delta H^\circ_{rxn} = \sum \Delta H^\circ_f(\text{products}) - \sum \Delta H^\circ_f(\text{reactants})