OpenEPIE 
In this episode, we describe the diffusion of a cylindrical solid in an unsteady state. First, we explain the Bessel equation to find the solution for Fick’s 2nd law in cylindrical coordinates. Then, we discuss how to calculate the concentration for various diffusion scenarios when the cylindrical solid diffuses only in the radial direction.
In this episode, we describe the diffusion of plate solids within a finite range. How would we calculate the concentration If the diffusion occurs in an unsteady state? To describe this, first, we find a solution for a PDE under specific conditions. Then, we utilize the solution to examine diffusion scenarios for various cases.
When dealing with the equilibrium of a specific system, we often utilize fugacity. In this episode, we discuss methods for estimating the fugacity of components and explore the vapor-liquid equilibrium in mixtures using the methods.
Equilibrium is a crucial thermodynamic concept, representing a state where there is no change over time when observed on a macroscopic scale. In this episode, we cover the equilibrium criteria based on different systems. Finally, we discuss the properties of a closed system (given temperature and pressure) at phase equilibrium.
In this episode, we discuss about diffusion in a plate solid under unsteady-state conditions. We will utilize Fick’s 2nd Law, a partial differential equation. First, we analyze diffusion in a plate solid with a finite thickness within an infinite medium. And we describe diffusion in a thin film within a semi-infinite medium.
There are differences between the actual properties and the ones in the ideal state. In this episode, we discuss the concepts of residual properties and excess properties that refer to the differences. Finally, we cover a new property called fugacity by comparing the property in the real state with the ideal state.
Thermodynamics allows us to analyze and predict various phenomena. In this episode, we describe the fundamental information required for understanding thermodynamics. Firstly, we discuss the definition and types of systems and the laws of thermodynamics. Finally, we summarize the relationships among thermodynamic properties.
The heat of reaction plays a significant role in heat (or energy) balance calculations. In this episode, we introduce the standard heat of formation and standard heat of reaction. And we discuss how to calculate the heat of reaction at a specific temperature. Finally, we describe how to calculate the heat balance with reaction through an example.
In this episode, we describe diffusion depending on the shape of solids in a steady state. Specifically, we cover the plate, cylindrical, and spherical cases. For each case, we derive the equation from Fick’s 2nd law and explain how to calculate diffusion.
The substance moves from one point to another due to various reasons such as pressure, temperature, and concentration gradients. In this episode, we will briefly discuss diffusion, which is the movement due to concentration gradients. We will introduce Fick’s 1st law, which is a law related to diffusion. Then, based on this law, we will derive Fick’s 2nd law, which describes the diffusion when the concentration changes over time.