Chem1 Virtual Textbook - What is entropy?
Great tutorial on entropy in the general chemistry context.
Chem1 Virtual Textbook - The second law of thermodynamicsGreat conceptual introduction to the 2nd Law of Thermodynamics.
Purdue University - Entropy and the 2nd & 3rd Laws of ThermodynamicsReally excellent tutorial on entropy change in the chemical thermodynamic context.
HyperPhysics - Entropy as Time's ArrowTopic Resources
16 questions
figures for classroom presentation