Free Heat of Reaction Calculator

Calculate the heat released or absorbed per mole of reaction from calorimetry data: total heat measured and moles of limiting reagent.

kJ
mol

Heat of Reaction per Mole

-500.0 kJ/mol

Heat of Reaction per Mole vs Total Heat Measured (q)

Heat of Reaction per Mole

Formula

ΔH_rxn = q / n

Where:

  • ΔH_rxn = heat of reaction per mole (kJ/mol)
  • q = total heat measured (kJ), negative for exothermic
  • n = moles of limiting reagent
  • This converts calorimetry data into a molar enthalpy value for the reaction.

    Example Calculation

    A reaction releases 50 kJ of heat using 0.1 mol of limiting reagent.

    1. 01ΔH_rxn = q / n
    2. 02ΔH_rxn = -50 / 0.1
    3. 03ΔH_rxn = -500 kJ/mol

    Frequently Asked Questions

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