All Questions
Tagged with water physical-chemistry
99
questions
5
votes
0
answers
121
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How do bubbles on water surface merge?
When we open a tap over a water surface, we get to see a lot of bubbles ("half merged in the water") coming out on the surface.
Now what I saw was that two such nearby half bubbles merge to ...
- 8,220
1
vote
4
answers
146
views
General Doubt. My doubt about combustion
When we give flame to a newspaper it burns readily. What we need for a fire (fuel, heat, Oxygen) is also known as the fire triangle. But why does the paper not burn when we pour boiling water over it? ...
- 47
0
votes
6
answers
149
views
Conservation of water?
I know that water can exist in various states (liquid, solid, ...) and can be in various places (clouds, oceans, ground, ...). What I want to know is whether or not the total number of water ...
1
vote
2
answers
317
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Effect of impurities on boiling and freezing points
When impurities like salt is added to water, the boiling point of water increases because of what I think is vapour pressure, though I know very little about that too. However, with the same analogy, ...
- 19
0
votes
0
answers
16
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Any method for measuring hydroxyl and hydroperoxyl radicals in water?
I am looking to irradiate water containing some amounts of iron and would like to measure the amount of hydroperoxyl and hydroxyl radicals produced in real time as a result of the irradiation. Is ...
- 1
1
vote
2
answers
200
views
Why do hot water droplets persist in cooler water?
I notice this phenomenon typically when mixing hot or warm water with cold water. Basically, tiny droplets of hot water travel inside the body of cooler water and persist. I have included a photo of ...
- 71
0
votes
0
answers
41
views
How many degrees of freedom does the water molecule have? [duplicate]
This is mainly a question about molar heat capacity. I've read many different values for the degrees of freedom of water, for example f = 12 on (https://en.wikipedia.org/wiki/Molar_heat_capacity).
But ...
- 73
1
vote
1
answer
51
views
Is it possible to use a water molecule's expansion/contraction effect with heat as a motor?
When water molecule is cooled, it is well known that it expands:
That's the reason the rocks in the desert explode in the cold of the night: the rocks have water inside that expands with cold and ...
- 113
1
vote
1
answer
751
views
What effect does salt have on the boiling speed of water?
My question is the following:
I have two pots. Pot A and pot B. I fill both of them with 1l (litre) of water. Now I add a table spoon of salt into pot A. Which water is going to start boiling first?
I ...
- 23
1
vote
0
answers
98
views
How much $\rm CO_2$ can you save by overfilling a SodaStream bottle? [closed]
For people who don't know what Sodastream is: SodaStream is a system where you can make your own soda at home using regular water and a CO2 cartridge. You put water in the special Sodastream bottle, ...
- 3,989
1
vote
2
answers
368
views
Bubbles formed in standing water in glass
I kept a cold standing water in a glass for a while to warm it up. After a while I returned to see that small minute bubbles have formed in the glass. On closer inspection, the bubbles seem to not ...
- 2,042
2
votes
2
answers
465
views
Why does bubble formation only happens at the point when vapor pressure becomes equal to atmospheric pressure during boiling?
I am a high school student and I am very confused about what's actually happening at the microscopic scale in an ideal solution when it's boiling?
Boiling as I understand at microscopic level is- ...
- 39
4
votes
1
answer
67
views
Asymmetrical meniscus in certain glassware
I work in a lab that does tests on water samples, and one test we do measures COD or Chemical Oxygen Demand. For quality control, we have a COD standard which contains a certain amount of Potassium ...
- 41
-1
votes
3
answers
173
views
If the melting point of Oxygen is -218 Celcius and the melting point of Hydrogen is -259 Celsius, why is the melting point of water 0 Celcius?
Forgive my ignorance, but my knowledge of Physics is not much, I am not even high-school level yet.
So, out of curiosity, I thought if water is H2O, 2 Hydrogen, and 1 Oxygen, then why is water's ...
- 109
-1
votes
2
answers
120
views
While washing clothes, does more water mean more cleaning? [closed]
While washing clothes, we are used to thinking that more soapy water would clean better. Adding more water feels wrong because it reduces the 'soapiness'. Does adding more water actually decrease the ...
- 12.5k