Systems and Energy
This section discusses different types of systems in thermochemistry and introduces the concept of internal energy.
Definition: A system is the area of focus in a chemical reaction, while the surroundings are everything else.
The page explains three types of systems: open, closed, and isolated. It also introduces internal energy (E) as the sum of kinetic and potential energy of particles in a system.
Vocabulary: Internal energy includes kinetic energy from molecular motion (translational, rotational, and vibrational) and potential energy from bonds and intermolecular forces.
The page concludes with formulas for calculating changes in temperature and energy, introducing the concepts of heat and work (W).









