| Term | Definition |
| energy | the ability to do work or produce heat |
| heat | transfer of energy in a process |
| enthalpy | heat content at constant pressure |
| enthalpy of reaction | heat absorbed or release by a chemical reaction |
| enthalpy of combustion | heat absorbed or released by burning (usually with O2) |
| enthalpy of formation | heat absorbed or released when one mole of compound is formed from the elements in their standard states |
| enthalpy of fusion | heat absorbed to melt one mole of solid to liquid @ MP |
| enthalpy of vaporization | heat absorbed to change 1 mole lipqiod to gas @ BP |
| system | area of the universe we are focusing on |
| surroundings | everything outside of the system |
| endothermic | energy is a reactant |
| exothermic | energy is a product |
| state function | a property independent of past or future behavior |
| Entropy | measure of disorder in the system |
| Gibb's Free Energy | amt of free energy to do work |
| thermodynamics | study of energy and its interconversions |
| work | force acting over distance |