MOL-010 · Thermodynamics Sample material

Entropy, the third law and transport phenomena

Entropy and probability, entropy as a measure of disorder, the third law of thermodynamics, negative temperatures; transport phenomena in gases: the mean free path of molecules, diffusion, internal friction (viscosity) and thermal conductivity.

Estimated time: 3 h 5 activities

Learning objective

Understand the statistical definition of entropy ($S = k\ln W$) and its connection with disorder.
Know the third law of thermodynamics and its consequences; become acquainted with the concept of negative temperature.
Learn to calculate the mean free path of molecules.
Study the laws of diffusion, viscosity and thermal conductivity and the kinetic-theory expressions for the transport coefficients.

Expected outcomes

Calculates entropy changes in ideal-gas processes and in heat exchange.
Explains that the third law implies the unattainability of absolute zero.
Estimates the mean free path at standard conditions and at low pressure.
Calculates mass, momentum and heat fluxes using the laws of Fick, Newton and Fourier; explains the dependence of the transport coefficients on pressure and temperature.

Interactive modelDiffusion and the growth of entropy

Activities

Lecture
Lecture · 1 h 20 min · required
Problem solving on the topics "The second law of thermodynamics" and "Thermal conductivity of gases"
Practice · 1 h 20 min · required
Determination of the coefficient of internal friction of liquids by Stokes' method
Laboratory · 2 h 15 min · optional
Entropy and enthalpy
Self-study · 6 h · optional
Final test
Test · 20 min · required · pass ≥ 70%

Completion conditions

  • Lecture
  • Problem solving on the topics "The second law of thermodynamics" and "Thermal conductivity of gases"
  • Final test — at least 70%