【Q&A】May 8, 2017
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This post was last edited by LQ198619 on 2017-5-7 19:05. Question: What is vapor-liquid equilibrium? Answer: When a liquid substance is placed in a sealed container, collisions between the molecules that have evaporated into the air, as well as between those evaporated molecules and the container walls, cause some of the gas molecules to return to the liquid. At a certain temperature, when the number of molecules that evaporate from the liquid surface into the air is equal to the number of molecules that return from the air back to the liquid at the same time, a dynamic equilibrium is established between the liquid in the container and the vapor on its surface. This dynamic equilibrium is known as vapor-liquid phase equilibrium, or simply vapor-liquid equilibrium. http://bbs.hcbbs.com/static/image/hrline/4.gif Special May Day event on Haichuan Network: “Remembering the Glorious Moments” http://bbs.hcbbs.com/thread-1774529-1-1.html (Source: Haichuan Chemical Forum) First round of voting for the creative ideas contest (use your mouse to influence the results) http://bbs.hcbbs.com/thread-1776507-1-1.html [Haixin Chemical Cup ★ Spring has arrived at Haichuan Chemical] Summary post of the 2017 scenery-sharing event (you can take a look at the local landscapes posted by users from various places in your free time) http://bbs.hcbbs.com/thread-1766484-1-1.html
It is a closed system composed of a mixture of n components, with gas and liquid phases coexisting. At a certain temperature and pressure, when the two phases reach equilibrium, the chemical potentials of each component in the gas and liquid phases tend to be equal.
When a liquid substance is placed in a sealed container, collisions between the molecules that evaporate into the air, as well as between those evaporated molecules and the container walls, cause some of the gas molecules to return to the liquid. At a certain temperature, when the number of molecules that evaporate from the liquid surface into the air equals the number of molecules that return to the liquid, a dynamic equilibrium is established between the liquid in the container and the vapor on its surface. This dynamic equilibrium is known as vapor-liquid phase equilibrium, or simply vapor-liquid balance.
Answer: When a liquid substance is placed in a sealed container, the molecules that evaporate into the air collide with each other as well as with the container walls, causing some of those gas molecules to return to the liquid. At a certain temperature, when the number of molecules that evaporate from the liquid surface into the air is equal to the number of molecules that return from the air to the liquid at the same time, a dynamic equilibrium is established between the liquid in the container and the vapor on its surface. This dynamic equilibrium is known as vapor-liquid equilibrium, or simply vapor-liquid balance.
At constant temperature and pressure, when the gas and liquid phases come into contact, the absorbent moves from the gas phase to the liquid phase. As the concentration of the absorbent in the liquid increases, the absorption rate decreases gradually, while the desorption rate increases gradually. After a considerable period of contact, the absorption rate becomes equal to the desorption rate; that is, the partial pressure of the absorbed substance in the gas phase and its concentration in the liquid phase no longer change. At this point, the gas and liquid phases reach an equilibrium state, commonly referred to as phase equilibrium.
A closed system composed of a mixture of n components, with gas and liquid phases coexisting, reaches equilibrium at a certain temperature and pressure; at this point, the chemical potentials of each component in the gas and liquid phases tend to be equal. It is more convenient to use fugacity: when the fugacity of component i in the gas phase and the liquid phase of a mixture is equal, it is called gas-liquid equilibrium.
When a liquid substance is placed in a sealed container, due to the collisions between molecules that evaporate into the air, as well as between the evaporated molecules and the container walls, some of the gas molecules return to the liquid. At a certain temperature, when the number of molecules that evaporate from the liquid surface into the air is equal to the number of molecules that return from the air back to the liquid at the same time, a dynamic equilibrium is established between the liquid in the container and the vapor on its surface. This dynamic equilibrium is known as vapor-liquid phase equilibrium, or simply vapor-liquid equilibrium.
When a liquid substance is placed in a sealed container, due to the collisions between molecules that evaporate into the air, as well as between the evaporated molecules and the container walls, some of the gas molecules return to the liquid. At a certain temperature, when the number of molecules that evaporate from the liquid surface into the air is equal to the number of molecules that return from the air back to the liquid at the same time, a dynamic equilibrium is established between the liquid in the container and the vapor on its surface. This dynamic equilibrium is known as vapor-liquid phase equilibrium, or simply vapor-liquid equilibrium.
The rate of liquid evaporation is equal to the rate of gas liquefaction
A closed system composed of a mixture of n components, with gas and liquid phases coexisting, reaches equilibrium at a certain temperature and pressure; at this point, the chemical potentials of each component in the gas and liquid phases tend to be equal. It is more convenient to use fugacity: when the fugacity of component i in the gas phase and the liquid phase of a mixture is equal, it is called gas-liquid equilibrium.