Chemical Equilibrium and Gibbs Free Energy — Lesson 4

This lesson covers the concept of chemical equilibrium and its application in calculating the composition of products in a reaction. It explains how to use the Gibbs free energy function to determine the equilibrium constant (KP) for a given reaction at a specific temperature and pressure. The lesson also discusses the use of standard Gibbs free energy and Gibbs free energy of formation in these calculations. An example is provided where the mole fraction of O2 is calculated for a temperature of 3000 K and a pressure of 1 atmosphere. The lesson concludes with a brief discussion on how to calculate adiabatic flame temperature.

Video Highlights

03:01 - Explanation of the concept of chemical equilibrium
07:03 - Discussion on the change in Gibbs function when pressure and temperature changes
11:49 - Explanation of the concept of extent of reaction and its role in determining the equilibrium condition
34:28 - Calculation of the equilibrium constant based on partial pressures
38:13 - Solving a problem involving the calculation of the equilibrium composition of products in a reaction

Key Takeaways

- Chemical equilibrium is achieved when the forward and reverse reactions occur at the same rate, resulting in a constant concentration of reactants and products.
- The Gibbs free energy function is used to determine the equilibrium constant (KP) for a given reaction at a specific temperature and pressure.
- The standard Gibbs free energy and Gibbs free energy of formation can be used to calculate the composition of products in a reaction.
- The mole fraction of a component in a reaction can be calculated using the equilibrium constant and the given temperature and pressure.
- The adiabatic flame temperature can be calculated by assuming a temperature and checking if the enthalpy of the products equals the enthalpy of the reactants.