Questions tagged [evaporation]
The process of a liquid changing to a gaseous state
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The Evaporation of Sessile Drops in Still Air due to molecular diffusion [closed]
A sessile drop on surface , evaporates due to molecular diffusion in constant contact area mode. Calculate molecular flux for different values of height of drop and contact angle , assume initial ...
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Is it possible to cool a hot drink by inhaling the steam from the drink?
Say we have a hot cup of coffee that is giving off steam. It is releasing heat into the environment through radiation and conduction. The steam is from certain particles reaching a high enough kinetic ...
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Can the Antoine equation be used without making vacuum?
The Antoine equation is a semiempirical formula, derived from the Clausisus-Clapeyron relation, which allows the vapor pressure $P$ of a pure substance to be approximated by
$$ \log_{10}(P) = A - \...
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Is it possible for an absorption refrigerator to pump heat to a reservoir that is at a higher temperature than the heat source used to run it?
Judging by the wiki page I get the feeling that this type of heat pump would not function if it's radiator were hotter than the heat source, but I can't quite put into words why and I feel like there ...
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Why does the boiling water in the pot get sucked up by the jar?
In order for the jars to be sterilized for pickling tomatoes, they need to be boiled. But when one of the inverted jars was standing on the rack in the pot, it started sucking in the water that was ...
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Why does blowing air on wet bodies dry it? [duplicate]
Suppose I blow dry a region with some water on it. Would it dry it faster than otherwise? If yes, why?
I can give one qualitative reason against it, since the blow dryer is blowing room temperature ...
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Why is vapor pressure well-defined?
(I am self-studying as can be verified from my post history and, additionally, I believe this question has more general applicability.)
Callen asks us to consider the following in his famous textbook:
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Pressure rise in a container as small amount of liquid is vaporized
How would one calculate pressure rise in some closed volume as small amount of liquid is added to it? Volume is initially in vacuum. Amount of liquid is not enough to get volume saturated. Let's say 1 ...
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Evaporation when the air is colder than the liquid water
I am currently thinking through evaporation over lakes, specifically the Laurentian Great Lakes (a complex subject, I know). Particularly, I am trying to wrap my head around why evaporation peaks in ...
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How does evaopration and diffusion affect concentration of solute at the solvent surface?
Imagine a long, thin tube with one end sealed and the other end open. It is filled with a volatile solvent with a dissolved non-volatile solute. As the solvent evaporates at the liquid surface, the ...
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If comets are thought to brought water on Earth could there be water in form of ice on the neighbouring Moon's poles?
If comets are thought to brought water on Earth could there be water in form of ice on the neighbouring Moon's poles? As water can easly evaporate if there is no atmosphere as in the case of Moon's ...
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How to understand this derivation of Raoult's Law?
A derivation of Raoult's Law in a textbook is as follows:
I cannot follow the chain of arguments: Why should $p_{A0}=p_{B0}$ ?
A and B are basically two different substances, each of which has a ...
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What is the physical reason for why hot air holds more water vapour, and how does this relate to saturation vapour pressure?
It is said that hot air holds more water vapour.
I guess this means that the saturation vapour pressure of water in air increases with temperature. Is this correct?
How can one derive this result? ...
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How does the drying of dishes outdoors by a cool wind on an overcast day relate to heat?
On a hot summer day, dishes dry outdoors almost immediately. At other times, a cool wind with an overcast sky will sometimes also dry dishes outdoors after a while. I am aware that some heat still ...
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What happens in a steam convection oven at 350 F?
Assume you have an oven chamber of fixed volume (let's say $1 \text{ m}^{3}$) which also releases any excess pressure. At the bottom is a tray that contains boiling water. You heat up the oven until ...
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Why water or condensation in a narrow neck open bottle can't seem to evaporate completely?
When I clean a soda bottle with water, empty the water out and leave the bottle open for days and the inside wall of the bottle seems to stay "wet" not "dry"?
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Vapor Pressure and Equilibrium
I am still fairly new to physics, and my questions might come foolish to the more professional; but these are honest questions that I feel restrained in understanding. I believe I partially got the ...
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Derivation of the Antoine equation
The vapour pressure $P^0$ of a pure substance can be approximated by a semi-empirical formula called the Antoine equation, which says $P^0$ is related to the temperature $T$:
$$ \ln(P^0) = A - \frac{B}...
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How has Earth's atmospheric water been in previous eras and periods?
How has partial pressure and net amount of water vapor and colloidal water been in previous eras and periods on Earth?
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Why does a small puddle of water evaporate faster at the edges than the center?
I have read that ceiling tile stains and coffee ring stains are darker on the edges than the center because the puddles evaporate fastest at the point of contact between the surface, air, and water ...
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I’m trying to humidify my house by evaporating water in a vessel on my wood stove. Will a lidded teakettle produce more or less vapor then a open pot? [closed]
I found a tea kettle that looks very nice on our wood stove but am thinking that using an open pot would be more efficient at humidifying the air due to the larger exposed surface of the water vs ...
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Gas expansion during phase change (intense boiling) relation to liquid level rasing to overboiling level of a container (Literature?)
I'm looking into the area of "slugging" in open-containers which are containing a pure substance undergoing a phase-change from liquid->Vapor. I'm trying to find a connection between ...
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Calculations about vacuum chamber heat pipes
Heat pipes, as seen in many laptops and computers are used for transferring the heat of the CPU to the fans.
On my house boat, I have a stove at one end. The other end could do with heating up too. I ...
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Disappearing cola in a hot car
I unadvisably left an unopened can of cola in my car on a very hot, sunny day. The top blew off and when i recovered the can it was clean and dry inside. Except for a few sticky droplets on the ...
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Why doesn't the number of $\rm H_2O$ molecules evaporated depend on the number of the other gaseous molecules?
I have a conceptual contradiction. Say we remove a partition between liquid water and gaseous nitrogen at constant volume and temperature. The average number of gaseous water molecules will increase ...
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Maximizing the smell of coffee in the morning
I bring coffee in a partially filled thermos. The hot coffee evaporates a bit into the cushion of air between the coffee and the lid, the air + coffee vapor mix heats up by heat exchange with the ...
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Air temperature drop by water mist cooling [closed]
if we have a volume of air (1m3/1'200g) at a certain temp (25°c) and let water evaporate into it, what is the max achievable air temp drop? how much water has evaporated (i guess i can calculate the ...
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Evaporation time for a Mercury-Ball
How long does it take for a Mercury-Sphere to evaporate, if it has a diameter of 1mm and the temperature is 25 Degrees Celsius and the air moves at a speed of 1km/h over it?
What would the formula for ...
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Amount of water vaporized when cooled down naturally
Suppose we have $m_i$ kg of liquid water at $100 °C$. This water cools down to $20 °C$. We want to estimate roughly the amount of water that would have to evaporate, in adiabatic conditions with the ...
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Could a window mounted wet cloth sheet chill a room?
Assuming there is a light wind, that construction is partly shaded and a constant water pouring and evaporation of the material is occurring due to the breeze.
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Why do clouds have well-defined boundaries?
Why do cumulus clouds have well defined boundaries? In other words, what are the physical mechanisms that hold a cloud together, as an entity separate from other clouds, that prevent it from spreading,...
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Most efficient method to evaporate a metal in a vacuum?
If one had a metal block (lets say tantalum) in a vacuum chamber, what would be the most efficient way of evaporating it in regards to the proportion of the input energy directly going into removing ...
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If gravity was lower but air density was the same, how would evaporation be affected?
I'm confused about the relationship between air density, air pressure and gravity.
Does water evaporate faster under low air pressure simply due to the air density being lower? If the air pressure was ...
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Does gas pressure impact the rate of evaporation?
As we know, evaporation occurs when a liquid molecule has a kinetic energy that is greater than the minimum amount of energy needed to overcome the intermolecular attractive forces holding it in the ...
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Why water vapor condenses on glass? [closed]
I've read an answer to this question that stated glass was colder than air, causing this transfer of energy from the vapor to the glass, creating this condensation. But why is the glass colder than ...
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Why do we feel cool after switching fan? [duplicate]
Please see that my actual question is not similar to this: Why do we feel cool when we turn our fans on?
Suppose I switched my fan on. The air particles start moving. Since, their kinetic energy ...
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Can oil "boil" in vacuum ? (Is it usable to make absolute (low) pressure measurement ?)
In order to measure vacuum absolute pressure, I thought about making a water column barometer, however, water will boil under high vacuum. Can I use oil instead ? On one side, I would expect any ...
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Does a metal evaporate as single atoms or as molecules?
If I had a liquid metal, like Al, and I begin heating it so it evaporates, would the evaporating Al be in the form of atoms or as molecules?
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When water is evaporated and the particles with a little more energy breaks away, Why do the molecules left have less motion?
From Feynman's Six easy pieces:
Then a molecule leaves it is due to an accidental, extra accumulation of a little bit more than ordinary energy, which it needs if it is to break away from the ...
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Why saturated vapor does not obey gas laws? [duplicate]
in my book it has mentioned "number of saturate molecules does not remain constant when the temperature changes(mass of vapor is not constant),therefor saturated vapor does not obeys gas law"...
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Non-Equillibrium thermodynamics in rapid evaporation of liquid by laser heating in vacuum chamber
I currently have some results that I am trying to understand. These results show the peak temperature of a crucible (w/ a 10mm diameter) filled with liquid Ag (see diagram). The surface of the liquid ...
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Steam Produced by Induction Cookers
I had recently noticed that induction cookers produce much more steam than normal gas tops and when I set the setting in the induction cooker to 'steam' it produces ever more steam. I used the same ...
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Effect of the temperature dependence of $\Delta H_{vap}$ on the vapor pressure?
I am aware that the enthalpy of vaporization of a fluid ,$\Delta H_{vap}$ is temperature dependent since it must be equal to zero at the critical temperature of said fluid, $T_c$ (although this is ...
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Convection from rapidly evaporating liquid inside vacuum chamber?
If we have a liquid that is is being actively heated and is rapidly evaporating (let's say around 1g/s for Ag at 1500K) inside a vacuum chamber, can convection around the liquid/vapor interface occur ...
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What causes the rim of the droplet to stop moving in the Marangoni effect?
This is specifically concerning a set-up where a droplet containing a mixture of water and alcohol is deposited on the surface of vegetable oil in a petri dish. I want to know what causes the inner ...
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Mystifying Relative Humidity - That can't be accurate?
While humidifying a room in my home, measuring the Temperature and Relative Humidity (T&RH respectively) every 8 hours, I noticed that RH rises and falls with T when it should be the inverse.
I ...
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How do I correlate the Rayleigh-Taylor instability with this Marangoni Bursting phenomenon?
The droplet was a water-isopropanol mixture of concentration 50% and was deposited on a 5mm thick layer of sunflower oil in a petri dish.
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Why is the latent heat of vaporization 0 at the critical point?
This is not a homework question.
The critical point of water is $\mathrm{374 \ C}$ and $\mathrm{22.06 \ MPa}$. At the critical point the latent heat of vaporization is $0$ - why?
Assume the water ...
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How much heat energy is required to bring 1 liter of water to the critical point?
This is not a homework question.
The critical point of water is 374 C and 22.06 MPa. At the critical point the latent heat of vaporization is 0 - why?
Assume the water starts at 100 C.
If you add the ...
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Why my glass spects or windows becone blurr in winter i.e cold weather due to my breath but NOT in summer i.e hot weather?and why disappear after?
I noticed than when I blow up on my spects it get blurr as water vapor condense onmy spects, but after some time it dissappear! How?
If water vapor at first place loose heat to my spects as my spects ...
