Entropy Unlike energy functions, entropy is not conserved in natural process or in isolated systems. For example, consider heat transfer between two objects with different temperature TI and TII (TI …
The total entropy, which is a summation of entropy of the system and entropy of the surrounding, is a determinant for the reversibility. The sign of total entropy determines if …
Does spontaneous process mean the fast process? A spontaneous process is simply a process that occurs without the need for additional energy. It does not mean that the process will …
Entropy is one of the thermodynamic functions that describe the condition of the system. What is entropy? What is the physical meaning of entropy? Entropy is related to degree of …
There are three thermodynamic status: unstable, stable and metastable. Unstable status will spontaneously change into stable or metastable status. Stable status is in energy minimum or equilibrium state, and will …
This video introduces the second law of thermodynamics, the entropy principle. The second law is concerned with the conversion of heat into work and the quality of energy. The quality …
Welcome to the Third week of the course. We are going to introduce the second law of thermodynamics. Last week, we overviewed the first law of thermodynamics: the energy principle. …
This week, you have practiced the calculation of energy changes using energy balance equations. Many exercises for the calculation of energy changes upon temperature change are presented. You learend how …
The equation of state for the ideal gases under adiabatic and reversible volume changes can be formulated in a very special form. The physical variables of ideal gases under adiabatic …
The P-V-T relationship for real gas needs modification of ideal gas laws. 1) Compressibility factor The compressibility factor Z is a correction term to the ideal gas laws. PV=ZRT, z …
Perpetual motion machine of the first kind is a machine that can do work indefinitely without an energy input. From ancient, people has been captivated by this concept. The examples …
An adiabatic process is one in which no heat is exchanged with surrounding. A special case is adiabatic flow through a valve. This is when the valve is insulated or …
The equation of state is the relationship among the physical variables that describe the condition of a material. The equation of state for ideal gases is presented. We can use …
Example : In a gas-spring system An ideal gas is contained in a cylinder. Initially the pressure, volume and temperature were P1, V1, and T1. A spring with a spring …
What is adiabatic flame temperature? When the chemical reaction is combustion reaction, heat is evolved from the reaction. This heat might be used to raise the temperature of the system …