This lesson investigates how scientists and engineers communicate information regarding enthalpy. You will learn some ways to communicate enthalpy changes for a given chemical reaction and you will begin to understand the importance of knowing the enthalpy of a chemical reaction per mole of reactant and/or product.

Enthalpy changes can be communicated in at least four ways:

1. Stating the enthalpy change for a balanced reaction equation
   
   
2. Stating the molar enthalpy of a specific reactant or product in a reaction
   
   
3. Including the energy value as a term in a balanced reaction equation
   
   
4. Drawing a chemical potential energy diagram