Standard Enthalpy of Reaction & Hess's Law Calculator (ΔH°rxn)
Calculate standard reaction enthalpy (ΔH°rxn in kJ/mol) from standard enthalpies of formation (ΔH°f) and classify reactions as exothermic or endothermic.
Standard Reaction Enthalpy (ΔH°rxn)
Calculator Inputs
Standard Reaction Enthalpy (ΔH°rxn)
Total Heat Transferred
Total Heat in Kilocalories
Exothermic Reaction: Releases thermal energy to the surroundings; products have lower potential energy and higher thermodynamic stability.
Reaction Energy Profile
Standard thermochemistry and chemical thermodynamics tool based on Hess's Law and formation enthalpies.
Calculation Methodology
Standard Enthalpy of Reaction: ΔH°rxn = Σ [ n_p * ΔH°f(products) ] - Σ [ n_r * ΔH°f(reactants) ]. Negative values indicate exothermic reactions; positive values indicate endothermic reactions.
Frequently Asked Questions
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