The key difference between microstate and macrostate is that microstate refers to the microscopic configuration of a thermodynamic system, whereas macrostate refers to the macroscopic properties of a thermodynamic system.
Microstate and macrostate are two forms of chemical concepts that are used regarding thermodynamic systems. Microstate of a thermodynamic system describes the microscopic properties of the system while macrostate describes the macroscopic properties. Generally, the properties of macrostate are averaged over many microstates.
CONTENTS
1. Overview and Key Difference
2. What is Microstate
3. What is Macrostate
4. Side by Side Comparison – Microstate vs Macrostate in Tabular Form
5. Summary
What is Microstate?
Microstate is a term that describes the microscopic properties of a thermodynamic system. In classical thermodynamics, it describes that thermodynamic systems are macroscopic systems containing macroscopic properties. However, all these thermodynamic systems are made up of atoms; therefore, it is very important to understand the microstate of the system as well, which specifies the quantum state of all the atoms in the system.
Figure 01: A Thermodynamic System
For example, the changes in the microstate can be as small as 1035 times than a macrostate, but there are still changes in this scale which may have no effect at the macrostate. A single macrostate contains a very large number of microstates. Therefore, one macrostate may contain several different microstates. In other words, we can predict the changes in the macrostate of the thermodynamic system via averaging the changes of microstates.
What is Macrostate?
Macrostate is the term that describes the macroscopic properties of a thermodynamic system. The most commonly measured macroscopic properties include temperature, pressure, volume and density. A macrostate is definitely larger than a microstate. As described above, some slight changes, which are large changes in the microstate, may not have a considerable change in the macrostate due to this size difference. Therefore, macrostates give a rough measurement of the thermodynamic system, instead of complete details with slight fluctuations.
Figure 01: Relationship between Microstate and Macrostate in Flipping a Coin Twice
Figure 1 indicates the relationship between microstate and macrostate regarding the process of flipping a coin twice. H refers to the “head” and “T” refers to the tail of the coin. All microstates are equally probable, but macrostate (H, T) is twice as probable as macrostates (H, H) and (T, T).
What is the Difference Between Microstate and Macrostate?
Microstate and macrostate are two forms of chemical concepts that are used regarding thermodynamic systems. The key difference between microstate and macrostate is that the term microstate refers to the microscopic configuration of a thermodynamic system, whereas macrostate refers to the macroscopic properties of a thermodynamic system.
Moreover, we can predict the changes in the macrostate of the thermodynamic system via averaging the changes of microstates. For example, the changes in the microstate can be as small as 1035 times than a macrostate, but there are still changes in this scale which may have no effect on the macrostate.
The following table summarizes the difference between microstate and macrostate.
Summary – Microstate vs Macrostate
Microstate and macrostate are two forms of chemical concepts that are used regarding thermodynamic systems. The key difference between microstate and macrostate is that the term microstate refers to the microscopic configuration of a thermodynamic system, whereas macrostate refers to the macroscopic properties of a thermodynamic system.
Reference:
1. “Microstates and Macrostates.” Theoretical Physics, University of Manchester, Available here.
2. “Microstate.” Microstate – an Overview | ScienceDirect Topics, Available here.
3. “Microstate (Statistical Mechanics).” Wikipedia, Wikimedia Foundation, 27 Dec. 2019, Available here.
Image Courtesy:
1. “Thermodynamic system01b” By Adwaele at English Wikipedia (CC BY-SA 3.0) via Commons Wikimedia
2. “Macrostates and microstates of two coins” By Mgunyho – Own work (CC BY-SA 4.0) via Commons Wikimedia