Gas Mixing & Entropy

This interactive simulator explores Gas Mixing & Entropy in Thermodynamics. Two species separated then mixed; ΔS = 2nR ln 2 for equal volumes and moles. Use the controls to change the scenario; watch the visualization and any graphs or readouts to connect the model with lectures, labs, and homework.

Who it's for: Best once you already know the basic definitions and want to build intuition. Typical context: Thermodynamics.

Key terms

  • gas
  • mixing
  • entropy
  • gas mixing entropy
  • thermodynamics

How it works

Mixing of distinct ideal gases at constant T increases entropy because each species spreads into twice the volume. Identical particles require quantum Gibbs paradox treatment; here we show the classical distinguishable mixing case.

Key equations

ΔS = n_A R ln(V_f/V_i) + n_B R ln(V_f/V_i)  ·  y_i = n_i / (n_A+n_B)