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Reaction Enthalpy (Hess's Law)
Calculate standard enthalpy of reaction ΔH°rxn from bond enthalpies or heats of formation.
Dr. Lena FischerVerified
PhD Chemistry (Analytical), MRSC
Analytical chemist with 12 years in pharmaceutical QA, spectroscopy, and solution chemistry. Passionate about making chemistry accessible.
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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})Was this helpful?0 found helpful