【Q&A】May 21, 2017
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Question: What is saturated vapor pressure? Answer: In any liquid, the surface molecules have a tendency to break away from the liquid surface and enter space, a process known as vaporization. At the same time, the spatial gas molecules generated also have a tendency to form a liquid due to their continuous motion, that is, liquefaction. Vaporization and liquefaction are two opposite processes that occur simultaneously. At a certain temperature, when the number of molecules that move into space equals the number of molecules that form the liquid, that is, when the relative amounts of vapor and liquid no longer change, a dynamic equilibrium is established between the vapor and the liquid. At this point, the vapor pressure above the liquid is the saturated vapor pressure of that liquid at that temperature. http://bbs.hcbbs.com/static/image/hrline/4.gif HaiChuan Network’s special May Day event, “Remembering the Glorious Moments,” warmly invites your participation. http://bbs.hcbbs.com/thread-1774529-1-1.html (Source: HaiChuan Chemical Forum) Summary post for HaiChuan Network’s special May Day event, “Remembering the Glorious Moments.” http://bbs.hcbbs.com/thread-1774532-1-1.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
The pressure of a vapor that is in phase equilibrium with a liquid or solid at a certain temperature under sealed conditions is called the saturated vapor pressure. The same substance has different vapor pressures at different temperatures, and these pressures increase as the temperature rises
At a certain temperature, when a liquid is in equilibrium with the vapor above its surface, the pressure generated by this vapor is called the saturated vapor pressure
The pressure of a vapor that is in phase equilibrium with a solid or liquid at a certain temperature under sealed conditions is called the saturated vapor pressure
Vapor pressure refers to the pressure exerted on the surface of a liquid (or solid) by the vapor of that substance present at its surface; this pressure is known as the vapor pressure of the liquid. For example, the surface of water has a vapor pressure; when this vapor pressure equals the total pressure of the gases above the water surface, the water boils. When we see water boiling, it is at 100 degrees Celsius, when the vapor pressure of water equals one atmosphere. The vapor pressure changes with temperature; the higher the temperature, the greater the vapor pressure. Of course, it also depends on the type of liquid. At a certain temperature, the pressure exerted by steam that is in equilibrium with the liquid (or solid) form of the same substance is called the saturated vapor pressure, and this pressure increases as the temperature rises. For example, the water in a cup will gradually decrease as it keeps evaporating. If pure water is placed in a sealed container and the air above it is removed. As water continues to evaporate, the pressure of the vapor phase above the water surface, that is, the pressure exerted by the water vapor, increases continuously. However, when the temperature is constant, the vapor pressure will eventually stabilize at a fixed value; this vapor pressure is known as the saturated vapor pressure of water at that temperature. When the value of the vapor pressure reaches that of the saturated steam pressure, water molecules in the liquid phase continue to vaporize, and water molecules in the vapor phase continue to condense back into a liquid. Since the rate of vaporization of water is equal to the rate of condensation of water vapor, the amount of liquid does not decrease nor does the amount of gas increase; thus, a balance is achieved between the liquid and the gas. Therefore, when the pressure of the vapor of a liquid pure substance equals its saturated vapor pressure, phase equilibrium is achieved between the vapor and liquid phases. Saturated vapor pressure is an important property of a substance, and its value depends on the nature of the substance and the temperature. The higher the saturated vapor pressure, the more volatile the substance is.
Saturated vapor pressure refers to the gas pressure (partial pressure) in a closed space, at a given temperature, when the liquid and gas phases of a substance coexist. At this point, the evaporation and condensation processes reach dynamic equilibrium.
The pressure of a vapor that is in phase equilibrium with a liquid or solid at a certain temperature under sealed conditions is called the saturated vapor pressure.
The pressure of a vapor that is in phase equilibrium with a solid or liquid at a certain temperature under sealed conditions is called the saturated vapor pressure. The same substance has different saturated vapor pressures at different temperatures, and these pressures increase as the temperature rises. The saturated vapor pressure of the pure solvent is greater than that of the solution ； For the same substance, the saturated vapor pressure in the solid state is lower than that in the liquid state.
The pressure of a vapor that is in phase equilibrium with a solid or liquid at a certain temperature under sealed conditions is called the saturated vapor pressure.
The pressure of a vapor that is in phase equilibrium with a solid or liquid at a certain temperature under sealed conditions is called the saturated vapor pressure. The same substance has different saturated vapor pressures at different temperatures, and these pressures increase as the temperature rises. The saturated vapor pressure of the pure solvent is greater than that of the solution ； For the same substance, the saturated vapor pressure in the solid state is lower than that in the liquid state.
Vapor pressure refers to the pressure exerted on the surface of a liquid (or solid) by the vapor of that substance present at its surface; this pressure is known as the vapor pressure of the liquid.