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The $\eta$ parameter described in $E_{cut}$ is completely arbitrary and set by the method of evaporation. In practice, it's usually an RF field (sometimes called the RF "knife") tuned to eject all atoms above $E_{cut}$, and the experimentalist sets some sort of profile for how quickly $E_{cut}$ decreases by changing the RF frequency. It seems to work best ...


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You have a 2 liter rigid container, featuring 1 liter of liquid water and, above it, one liter of a mixture of air and water vapor all at 1 atm. The temperature is 20 C, and the partial pressure of the water vapor in the head space is the equilibrium vapor pressure, so that the system is at equilibrium. This is the initial thermdynamic equilibrium state of ...


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Let's say that you have a vessel containing water and air and you start heating it. The temperature of the water and air inside will start to rise and so will the pressure, because the air would like to expand (but volume is fixed and water is almost incompressible). Since the boiling point of a substance depends on both pressure and temperature (for example ...


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I am not sure if I could understand your meaning. I think you ask about a situation that the water phase changes from liquid to the gas without passing across two phase region. If the pressure is greater than the critical pressure, then there is no distinct phase-change (boiling) process. You can see this as below figure from “THERMODYNAMICS An Engineering ...


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If you put earthen pot in water before water inside pot reaches surface, then Yes, cooling will become faster. For instance, your hot utensil cools when plunged in water. But, final temperature of water inside pot is independent of above two ways of cooling.


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I guess your question is how to increase evaporation amount because the time is the droplet traveling time. To increase evaporation amount without changing air condition, followings can be considered. reduce droplet size: the evaporation rate is proportion to $\frac {1}{D^2}$, where D is droplet diameter. increase droplet speed: this can increase ...


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If air temperature is higher than the pot temperature, it can be cooled. This is especially true in summer time when temperature is high and vapor pressure is low. When air flow over the top of the water surface, it carries away vapor (reducing partial pressure, in thermodynamics). The water evaporates. The phase change needs heat that cool down both air ...


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Some water will evaporate, and the heat required for this comes from the water itself. The water will cool down a little (latent heat of evaporation is a function of temperature, going from about 45 kJ/mol at 0 °C to 40.7 kJ/mol at 100 °C). The heat capacity of water is about 75 J/mol K. This means that evaporating one gram of water would extract enough heat ...


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When pressure is below the vapor pressure, evaporation occurs. Accompanying to phase change (evaporation), heat is required, which reduces the water's temperature and its vapor pressure needs to be even lower. So you need continue to reduce pressure in order to keep evaporation continue. Otherwise, it will stop. When it reaches or lower (transient) than ...


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Some of the water will evaporate. Keep in mind that not all of the water molecules have the same energy, some are moving faster than others. The temperature measurement indicates the average energy of the water molecules. When the piston is lifted, some of the faster molecules will escape the liquid to become water vapor. The remaining molecules have a ...


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While the answer of wbeaty is very interesting in showing points relevant in practice, I think all the answers are still missing an important and simple theoretical point, which you should consider to understand the process. vapour pressure does mean two different things as used above. First, the pressure, the existing water vapour would have (if it were ...


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When the vapor pressure is equal to the external pressure, there will form a bubble. Not true. Instead, when the vapor pressure is equal to the external pressure, then any existing bubbles will begin growing continuously. And, if no bubbles are already present, then the water will superheat far above the boiling temperature, yet no bubbles will ...



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