2H2O2 = 2H2O + O2 - Reaction Thermochemistry Calculator

Thermodynamic Analysis Results

Chemical Equation:

Automatic Calculation (Database Values)

Thermodynamic Analysis
Property	Value	Interpretation
ΔH°_rxn Enthalpy Change	-196.06 kJ/mol	Exothermic reaction: Heat is released to the surroundings
ΔS°_rxn Entropy Change	345.05 J/(mol·K) (0.3450 kJ/(mol·K))	Entropy increases: The system becomes more disordered
ΔG°_rxn Gibbs Free Energy Change	-474.28 kJ/mol	Spontaneous reaction: The reaction can proceed without external energy input

Thermodynamic Relationship:

ΔG° = ΔH° - TΔS°

ΔG° = -196.06 - (298.15)(0.3450) = -298.94 kJ/mol

⚠ Note: Some values may be from different temperature/pressure conditions

Step-by-step Calculation
Calculation Steps
Step 1: Apply thermodynamic formulas ΔH°_rxn = Σ ΔH°_f(products) - Σ ΔH°_f(reagents) ΔS°_rxn = Σ S°(products) - Σ S°(reagents) ΔG°_rxn = Σ ΔG°_f(products) - Σ ΔG°_f(reagents) Step 2: Calculate enthalpy change (ΔH°) ΔH°_rxn = Σ[coef × ΔH°_f(products)] - Σ[coef × ΔH°_f(reagents)] ΔH°_rxn = [2 × ΔH°_f(H₂O(l)) + ΔH°_f(O₂(g))] - [2 × ΔH°_f(H₂O₂(l))] ΔH°_rxn = [2 × (-285.83) = -571.66 + (0)] - [2 × (-187.8) = -375.60] ΔH°_rxn = -196.06 kJ/mol Step 3: Calculate entropy change (ΔS°) ΔS°_rxn = Σ[coef × S°(products)] - Σ[coef × S°(reagents)] ΔS°_rxn = [2 × S°(H₂O(l)) + S°(O₂(g))] - [] ΔS°_rxn = [2 × (69.95) = 139.90 + (205.147)] - [] ΔS°_rxn = 345.05 J/(mol·K) Step 4: Calculate Gibbs free energy change (ΔG°) ΔG°_rxn = Σ[coef × ΔG°_f(products)] - Σ[coef × ΔG°_f(reagents)] ΔG°_rxn = [2 × ΔG°_f(H₂O(l)) + ΔG°_f(O₂(g))] - [] ΔG°_rxn = [2 × (-237.141) = -474.28 + (0)] - [] ΔG°_rxn = -474.28 kJ/mol Step 5: Verify using ΔG° = ΔH° - TΔS° ΔG°_calc = -196.06 - (298.15)(0.3450) ΔG°_calc = -298.94 kJ/mol ⚠ Small differences may be due to temperature/pressure variations in data

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Reaction thermochemistry involves calculating the energy changes that occur during chemical reactions. The key properties calculated are:

Enthalpy change (ΔH°): The heat absorbed or released during a reaction at constant pressure
Entropy change (ΔS°): The change in disorder of the system during the reaction
Gibbs free energy change (ΔG°): Determines if a reaction is spontaneous or requires external energy

These calculations use standard formation data at 25°C (298.15 K) and 1 atm pressure.