Lesson Plan: Hess’s Law Chemistry • First Year of Secondary School
This lesson plan includes the objectives, prerequisites, and exclusions of the lesson teaching students how to define and use Hess’s law to calculate enthalpy changes.
Objectives
Students will be able to
- define Hess’s law,
- express equivalent energy changes on diagrams representing Hess’s law,
- use standard enthalpies of combustion to calculate standard enthalpies of formation,
- use standard enthalpies of formation to calculate standard enthalpies of reaction,
- use combinations of other standard enthalpies in the creation of Hess’s cycles,
- compare enthalpy change answers calculated from standard enthalpy changes to those calculated from bond energies.
Prerequisites
Students should already be familiar with
- enthalpy and energy changes,
- standard enthalpy change definitions.
Exclusions
Students will not cover
- entropy.
