Chemical Energetics

3.1 Heats of Combustion, Neutralization, Reaction and Solution

Energy content of common fuels.

• Wherever possible these terms should be introduced through experiments.

3.2

Simple energy level diagrams

3.3 Hess' Law

Experimental justification and simple calculations.

• The relationship of Hess' law to energy level diagram and thermo-chemical cycles should be brought out.

3.4

Students should be made aware that delta-H is not the sole driving force in a reaction and that endothermic reactions proceed spontaneously.

• Only delta-H is considered in this section.

For reactions of gases (enthalpy of reaction at constant volume) and delta-H (enthalpy of reaction at constant pressure are not the same but the difference can be ignored. Most laboratory experiments are done at constant pressure and delta-H changes are measured.