In this lesson our instructor talks about entropy and free energy. First, he discusses entropy, heat flow, and the second law of thermodynamics. Then he talks about the third law of thermodynamics, problem-solving involving entropy, and Gibb's free energy. He ends the lesson with a summary and three helpful sample problems. Entropy & Free Energy Nature favors states of low energy and high entropy. Entropy is related to disorder or chaos, and is the focus of the second and third laws of thermodynamics. There are a series of equations that allow us to calculate both entropy andGibb’s free energy under a given set of conditions.