Questions tagged [evaporation]
The process of a liquid changing to a gaseous state
244
questions
0
votes
1answer
24 views
+50
How does a moisture-wicking base layer reduce the evaporative cooling effect?
I read that moisture wicking base layers help keep you warm by keeping you dry, and therefore countering the effect of evaporative cooling.
That made sense to me, until I SPECIFICALLY read somewhere ...
0
votes
0answers
37 views
Would Isopropyl Alcohol (IPA) in a sealed tube dissipate over time?
A glass tube is filled with a sample of clean steam condensate. The water in the tube is tested for Total Organic Carbon (TOC). The result for the TOC test is positive for TOC with 500ppb. Hypothesis ...
0
votes
0answers
31 views
Evaporating black hole - slower than expected by simple description [duplicate]
In the simple description of how a black hole evaporates, one particle of a pair that spontaneously forms forms inside the event horizon and the other outside. The one inside can’t escape. The one ...
0
votes
1answer
49 views
How does sweat evaporate even when the relative humidity is 100%
Recently I entered a room at my workplace with sweaty clothes.The thermostat read 5°C and the humidity was 100%.The outside temperature was close to 20°C.Also the AC was switched off.In about ten ...
2
votes
3answers
74 views
Conduction, convection, radiation: Does evaporation count as one of those?
The forms of heat transfer are traditionally described as conduction, convection, and radiation. Is evaporation (or any other change of state) counted as one of those forms? Or is it considered its ...
0
votes
1answer
16 views
Which gas has the potential of having high content of water vapor molecules?
Air can contain a certain amount of water vapor molecules.
I want to know that which any other non-hazardous gas can adsorb very more amount of water vapor molecules?
2
votes
0answers
38 views
How does a heated lid in a thermal cycler prevent evaporation?
A thermal cycler is a chemistry lab device that increases or decreases the temperature of the material inside it. The lid of the device is heated to prevent condensation and evaporation of the mixture ...
5
votes
1answer
464 views
Is evaporation a kind of phase transition?
When liquid is heat up to a critical temperature $T_{c}$, it starts boiling and converting to gas. In statistical mechanics, we learn that it is a phase transition. We studied all the properties near ...
0
votes
1answer
65 views
Evaporating tungsten wire
Consider an incandescent bulb having a thin filament of tungsten that is heated to high temperature by
passing an electric current. The hot filament emits black-body radiation. The filament is
...
3
votes
1answer
46 views
Why does water start to evaporate after I turned off the stove (see details)?
I observe this every day. I heat water by first pouring it in a pan (made of aluminium, not that I think this detail is important). I put the pan on top of a flame, originating from natural gas. After ...
0
votes
0answers
32 views
What happens when a black hole evaporates?
I have read other articles here on the subject and I think my question is different..
When a singularity evaporates enough to reach just above the limit of mass required to make the singularity, what ...
0
votes
1answer
34 views
Evaporation cooling dynamics
I have a liquid (say, water) and a gas (say, air) at the same temperature. How will the temperature of either evolve over time? What's the steady-state of relative temperature of liquid and gas with ...
4
votes
1answer
96 views
Cooling effect caused by evaporation
Evaporation is said to cause cooling effect because it absorbs energy from surroundings to change its phase from that of a liquid to gas. I am in doubt as to why would the surroundings be ready to ...
0
votes
1answer
16 views
Do different liquids have different distributions of kinetic energy of their particles, and does this influence their vapor pressure significantly?
This is a bit of a cross-over between a physics and a chemistry question.
When we say a liquid has temperature $T$ we make a statement about the mean kinetic energy of a particle in that liquid. That ...
0
votes
2answers
51 views
Exact mode of evaporation
I am having a doubt regarding what is the exact mechanism of cooling during evaporation. At one place it is said that as surface water molecules evaporate it takes heat from surroundings and hence ...
3
votes
0answers
86 views
Condensed water freezes and other water condenses around it
So I was on a plane and tiny crystals of ice formed on the window glass. This window is formed by a few screens of glass (maybe or maybe not) with vacuum inside. I think the frost was due to some ...
3
votes
3answers
140 views
Does water boil faster in a shallow wide pan or a deep pot
I make my own Maple syrup and have to boil away lots water from the sap to make syrup. I have a propane burner and a wide roasting pan and a deep stew pot, both hold about the same amount of sap.
My ...
0
votes
0answers
115 views
How long would it take for a cup of water to fully evaporate?
How long does it take for a cup of water to evaporate?
To answer this question, I'll assume some basic parameters, and that the water is blown on by a fan, to arrive at an estimate:
Water volume: $...
0
votes
2answers
160 views
Should I walk or run to my towel when naked and wet? [closed]
This morning when I got out of the shower, I realised I had left my towel in the bedroom. Naked and wet I ran as fast as I could to get the towel. On my way back I didn't run, but rather walked, and ...
3
votes
1answer
82 views
Cause of change of tea volume during cooling
At work I often drink tea, and i usually fill my cup to the brim with boiling water. When I let it cool though, until it's ready to drink, the liquids surface has sunken by about a fingers width.
To ...
2
votes
3answers
110 views
If I leave a glass of water out, why do only the surface molecules vaporize?
If I leave a glass of water out on the counter, some of the water turns into vapor. I've read that this is because the water molecules crash into each other like billiard balls and eventually some of ...
0
votes
1answer
112 views
Does water need oxygen to evaporate?
For example, if you had a thick piece of glass and it had a kind of reservoir inside with half water and half space allowing the water to move but not escape from the inside of the glass, and then you ...
-1
votes
1answer
16 views
can we create an artificial cloud by evaporating ground water?
I need a clarity about whether an artificial cloud can be made by human or not,if it is so, then it will be useful for many.
1
vote
1answer
35 views
On the evaporation of fluids
Q. In which portion (1,2,3) there will be maximum concentration of evaporated water droplets? Or there will be uniform distribution of droplets?
Background:
Today, I noticed something really strange ...
2
votes
1answer
50 views
How do salt crystals evaporate in water?
Salt dissolves in water but when water has evaporated it is still there. What has happened
to the salt in the water and why is it still there when water has evaporated?
0
votes
1answer
129 views
Why did the liquid disappear from some unopened aluminum cans? My experience (read below) has not been answered [duplicate]
I’m posting my question because I read this original post. The post was from 2016, so I’m reposting in hopes that someone can answer. Here’s the original post: (Also, do not flag as duplicate. If you ...
0
votes
0answers
35 views
Water vapor pressure in oxygen bubble
Suppose we have a source of O$_2$ bubble formation in water at specific nucleation sites, how can we estimate the water vapor pressure inside the O$_2$ bubbles?
I know that:
(1): $p_\mathrm{O_2}+p_\...
0
votes
2answers
141 views
Relative humidity, definition and its dependence on state variables
Relative humidity ($RH$) is defined by the following equation:
$$ RH = \frac{p_{vap}}{p_{sat}} $$
Where $p_{vap}$ is the vapour pressure and $p_{sat}$ is the saturation vapour pressure.
VAPOUR ...
0
votes
4answers
92 views
When is it more efficient to blow air over a wet laundry in order to dry it - when it's wetter or when it's drier?
If I want to speed the drying of laundry and allocate for it one hour of fanning - should I use it just after I hang it to dry or several hours later?
When we want to cool hot tea it's better to add ...
5
votes
1answer
60 views
Why does salt ions is not exist at vapor when the water is boiled and evaporated?
I would like to understand when the water is boiled only pure vapor is produced and ions do not exist with vapor. Why?
Can't the ions stick to water vapor?
And
Are Na+ and Cl- have boiling points? ...
2
votes
0answers
38 views
Rate of direct (non-thermal) photon-induced evaporation of water?
I have read a long time ago of early experiments in the evaporation rate of surface water, and a discovery that in addition to the Sun's impact on the temperature of the water, it was believed that ...
0
votes
1answer
227 views
Evaporation rate of water with forced convection
A steel pot (diameter 200 mm) is fully filled with water (2 kg of water) and the water is maintained at a constant temperature of 40°C by supplying heat from an electrical tabletop burner.
Assume ...
0
votes
1answer
186 views
Why do we sweat on a hot and humid day but the clothes are able to dry?
I know that on a humid day,water vapour content is high in air and as a result evaporation of sweat is lesser and hence we feel hotter. What I am not able to get is, if water vapour content is high,...
1
vote
1answer
52 views
Can we enhance evaporation rate with a vacuum pump?
First, consider having water at 100C and 1atm and a heat source. If more heat added to water, we have more evaporation rate according to the following formula:
$$Q_{in}=m_{vapor}*h_{fg}$$
THEN
...
2
votes
1answer
69 views
Water at 0 atmospheric pressure
Suppose I put a bucket of water on the surface of the Earth. Then somehow the atmosphere disappears. My question is:
Would the water fly out of the bucket, or would it be still there?
My reasoning ...
1
vote
1answer
112 views
Amount of steam generated using gas burner and Induction cooker
I did an experiment by boiling water using two different heat sources.
At first, I boiled water using a gas stove, then I repeated by using an induction cooker.
I noticed that the amount of steam (...
0
votes
1answer
45 views
Effect of pressure when drying wet clothes in a windy environment
When we hang wet clothes outside, they dry faster if it is windy.
The wind causes forced convection and removes the air saturated with vapor, and the rate of evaporation does not decrease much in ...
2
votes
0answers
49 views
Why perspiration drops are seen in shopping bag?
Why perspiration drops are seen in shopping bag?
When i put hot bread in shopping bag after sometime i saw perspiration drops in the shopping bag.
1
vote
1answer
46 views
Will having two water pans in my smoker make any difference?
I have a backyard smoker, and I use a tray of water in it as thermal mass to help keep the temperature stable. I don't think the size of the tray is going to matter, but it's roughly 40cm x 30cm x ...
1
vote
2answers
62 views
Potential Energy of Particles
I read the following statement in my textbook
While a liquid is boiling, the energy supplied to the liquid goes to breaking the bonds between neighbouring molecules.
Can anyone explain the process ...
4
votes
4answers
262 views
Once a black hole is formed, is there anything other than Hawking radiation which shortens its life?
Hawking radiation is supposed to very slowly evaporate a black hole (terms and conditions apply :] ).
Apart from Hawking radiation, is there any mechanism or effect that can make a black hole cease ...
1
vote
2answers
449 views
What happens at the molecular level during evaporation?
During boiling the liquid gets its energy from the heat source so it can break the force between molecules and turn into gas while evaporation happens at the top of the liquid at any temperature. ...
0
votes
1answer
35 views
Does the presence of a flame affect the flow rate of gas out of a lighter or torch?
If I were to set a propane torch's valve to a fixed open position, would it run out of gas faster lit or unlit? Does the flame produce any kind of pressure change that affects the flow rate through ...
1
vote
1answer
41 views
Evaporation amount of water for a Storm [closed]
How much water from the ocean is evaporated for a storm over water?
I am trying to figure out what conditions will cause the most evaporation or how to calculate the amount of water evaporated for a ...
7
votes
0answers
484 views
Can a substance have zero vapour pressure above absolute zero?
According to this Reddit thread, the answer is no, vapor pressure can't be zero when temperature is above absolute zero. I suspect the answer might actually be yes according to a precise definition I ...
2
votes
3answers
642 views
Will water in a vacuum evaporate continously?
Will a vacuum chamber that is maintained at 0.1 Atmospheres with an open water container inside ever reach 100% humidity of the remaining air, so that no more water evaporates or will water ...
5
votes
1answer
84 views
Simple question about molecules leaving a liquid at a temperature below the boiling point
My textbook asks the question why a liquid cools down when partial evaporation occurs just below the surface at a temperature below the boiling point.
The answer is of course that only those ...
1
vote
1answer
61 views
Temperature Proxy (Climate)
At the bottom of the wikipedia article on climate proxies there is this formula:
$$
\delta \, {\rm ^{18}O} = \frac{\frac{\left[\rm{^{18}O}\right]}{\left[\rm{^{16}O}\right]}}{\frac{\left[\rm{^{18}O}\...
0
votes
1answer
45 views
Calculating gas pressure following water transformation to vapor (in contact with boiling oil)
When water falls into a pot of boiling oil, it turns into vapor, and in an enclosed space this will create a higher gas pressure. Is there a way to figure out how high of a gas pressure there will be ...
0
votes
1answer
66 views
What type of heat is efficient to evaporate water?
I found that there are several type of heating element in a hair dryer, but basically I mainly classify them into two ways of heat transfer: Radiation and Conduction.
The conventional hair dryer uses ...
