The Boltzmann constant ($k_B$) is a fundamental physical constant that relates the average kinetic energy of particles in a gas with the temperature of the gas. It is central to the kinetic theory of gases and has a value of approximately $1.38 \times 10^{-23}$ J/K.
Ideal Gas Law: An equation of state for an ideal gas, given as $PV = Nk_B T$, relating pressure (P), volume (V), number of molecules (N), and temperature (T).
Kinetic Theory of Gases: A theory that models gases as collections of many small particles whose motions obey Newton's laws and provides insight into concepts like temperature and pressure.
Entropy: A measure of disorder or randomness in a system, often represented by $S = k_B \ln \Omega$, where $\Omega$ represents possible microstates.