Enthalpy Change Calculator (ΔH) - Thermochemistry
Calculate the enthalpy change of a chemical reaction (ΔH) using standard enthalpy of formation values. Thermochemistry calculator for chemistry students with Hess's Law support. Includes bond enthalpy calculations and calorimetry for exothermic and endothermic reactions.
Hess's Law (ΔHf° Data)
ΔHreaction = Σ(n × ΔHf° products) - Σ(m × ΔHf° reactants)Variables:
- ΔHreactionReaction enthalpy changeReaction enthalpy change
- ΔHf°Standard enthalpy of formationStandard enthalpy of formation
- n, mReaction coefficientReaction coefficient
How to Use
- 1
Tulis Persamaan Reaksi
Pastikan reaksi sudah setara.
- 2
Input Data Produk
Enter koefisien and ΔHf° for setiap produk.
- 3
Input Data Reaktan
Enter koefisien and ΔHf° for setiap reaktan.
- 4
Calculate
Dapatkan ΔH reaksi total.
Examples
Pembakaran Metana
Problem:
CH4 + 2O2 -> CO2 + 2H2O. ΔHf: CH4=-74.8, CO2=-393.5, H2O=-241.8, O2=0.
Solution:
- 1.Produk: 1(-393.5) + 2(-241.8) = -877.1
- 2.Reaktan: 1(-74.8) + 2(0) = -74.8
- 3.ΔH = -877.1 - (-74.8)
Result:-802.3 kJ/mol
Reaksi eksoterm (melepaskan panas).
Frequently Asked Questions
What is reaksi eksoterm?
Reaksi yang melepaskan kalor (ΔH negatif), suhu lingkungan naik.
Berapa ΔHf° unsur bebas?
Nol. (Example: O2, N2, Fe solid memiliki ΔHf° = 0).