Energy: the capacity to do work or generate heat

Energy Measurements: Calories (Cal) or Joules (J). 4.184 J = 1 Cal.

Law of Conservation of Energy: Energy is neither created or destroyed. It is always conserved during a change. Energy can be converted from one form to another, but never lost.

Potential Energy: energy that results from an object’s position or configuration. A chemical bond is a form of Potential Energy.

Kinetic Energy: the energy of movement. The energy which a mass possesses due to its motion.

Thermal Energy: A type of Kinetic energy. The motion of atoms.

Heat: form of energy that is transferred from a body at a high temperature to a body at a lower temperature.

System: part of the universe upon which we focus our attention. Heat energy can flow in or out of the system depending on whether the system or surrounding is warmer.

Surroundings: the rest of the universe other than the system.

Endothermic process: heat flows from the surroundings into the reaction system.

Exothermic process: heat flows out of the reaction system into the surroundings.