Ludwig Boltzmann defined entropy as a measure of the number of possible microscopic states (microstates) of a system in thermodynamic equilibrium, consistent with its macroscopic thermodynamic properties, which constitute the macrostate of the system. A useful illustration is the example of a sample of gas contained in a container.

2018年12月21日 · Entropy (\(S\)) is a state function that can be related to the number of microstates for a system (the number of ways the system can be arranged) and to the ratio of reversible heat to kelvin temperature. It may be interpreted as a measure of the dispersal or distribution of matter and/or energy in a system, and it is often described as ...

2025年1月20日 · Ludwig Boltzmann developed a molecular-scale statistical model that related the entropy of a system to the number of microstates possible for the system. A microstate (\(\Omega\)) is a specific configuration of the locations and energies of the atoms or molecules that comprise a system like the following:

Determine relative entropies of different substances with respect to their physical state and complexity of the molecule. Predict the sign of ΔS of a system for a given chemical or physical process.

By this description, microstates in which all the particles are in a single box are the most ordered, thus possessing the least entropy. Microstates in which the particles are more evenly distributed among the boxes are more disordered, possessing greater entropy.

Entropy is a measure of the information that we lose when we describe the system in terms of macrostate variables. For example, suppose we describe our system in terms of the internal energy, volume, and number of particles U, V, N. Then the number of microstates for that value of U, V, N is called Ω(U, V, N), and the entropy is defined1 as.

Entropy is the level of randomness (or disorder) of a system. It could also be thought of as a measure of the energy dispersal of the molecules in the system. Microstates are the number of different possible arrangements of molecular position and kinetic energy at a particular thermodynamic state.