The joule per mole (symbol: J·mol−1 or J/mol) is the unit of energy per amount of substance in the International System of Units (SI), such that energy is measured in joules, and the amount of substance is measured in moles.
Division by the number of moles facilitates comparison between processes involving different quantities of material and between similar processes involving different types of materials.
The precise meaning of such a quantity is dependent on the context (what substances are involved, circumstances, etc.
[5] For this reason, it is common within the field of chemistry to quantify the enthalpy of reaction in units of kJ·mol−1.
[6] Other units sometimes used to describe reaction energetics are kilocalories per mole (kcal·mol−1), electron volts per particle (eV), and wavenumbers in inverse centimeters (cm−1).