Microstates & Macrostates

Why disorder wins

An interactive lesson with 6 steps, about 5 minutes: you predict, drag and solve, with instant feedback on every answer. It runs in your browser and needs JavaScript.

What you’ll learn

• A macrostate is a coarse description containing many microstates.
• Entropy $S = k_B \ln W$.
• The second law is overwhelming probability: systems move to macrostates with more microstates.

Steps

1. Two levels of description
2. A hundred coins
3. Molecules finding their way
4. Boltzmann’s entropy
5. Entropy of spreading
6. Gas in a box