Chemistry
Advanced

Hess Law

Total enthalpy change is the sum of step changes.

Formula

ΔH=∑ΔHsteps\Delta H = \sum \Delta H_{steps}

Variables

\Delta HEnthalpy change

Example

Path-independent energy

Did You Know?

Hess's law lets chemists add reaction energies like accounting entries, since total enthalpy ignores the route taken.

thermochemistry