We were inspired by Dr *Matthew Stoltzfus’s* approach in flipped classrooms, here at KFUPM we adapted similar approach. Dr. Fus thankfully agreed to share his video lectures with us.

The following videos are organised by sections of “Chemistry, by Julia Burdge”

**18.1 Thermodynamics**

The first law of Thermodynamics provides the means for accounting for energy, but it gives no hint as to why a particular process occurs in a given direction. A process is considered to be spontaneous if it occurs without outside intervention, and the driving force for a spontaneous process is an increase in entropy. We can define entropy as the measure of randomness or disorder and entropy can be expressed mathematically using macro/microstates and we can also compare the entropy of various systems.

**18.1 Spontaneous Process and Entropy**

**18.2 Quantitative definition of entropy**

Show PHET tutorial of an ideal gas.

**18.2 Qualitative definition of entropy – Part 1**

**18.2 Qualitative definition of entropy – Part 2**

The second law of Thermodynamics states that in any spontaneous process there is always an increase in entropy of the universe.

**18.4 The second law of thermodynamics**

The third law of Thermodynamics states that the entropy of a pure crystal at zero degress kelvin is zero. The change in entropy of a reaction can be calculated from the standard entropy of each substance.

**18.4 The third law of thermodynamics**

Gibbs Free Energy is a state function combining enthalpy and entropy in the form of G = H – TS. J. Willard Gibbs developed this equation, which provides a convenient way to use the change in enthalpy and change in entropy to predict whether a given reaction occurring at constant pressure and constant temperature will be spontaneous. The derivation of this equation can be seen below.

**18.5 Gibb’s free energy change, ΔG – part 1**

We can also consider the various situations for the relative signs of ΔH and ΔS to predict how ΔG will change with temperature. We can use the chart generated in the video below to investigate the effect of temperature on the spontaneity of a chemical reaction.

**18.5 Gibb’s free energy change, ΔG – part 2**

**18.5 Using ΔG and ΔG ^{o} to solve problems**