Two Hydrogen atoms covalently bonded to one Oxygen atom. One of the more common compounds on the surface of the earth.

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Why does frozen water burst a pipe?

When water freezes in a pipe it can crack the pipe open. I assume this takes quite a lot of energy as when I try to crack a pipe it can be hard work! I think water freezing is a result of energy ...
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2answers
334 views

Practical (maybe naive) question on boiling water

I put a glass bottle in a big pot, bottleneck up, I fill both pot and bottle with very hot water. The bottle is submerged except a few cm of the bottleneck and filled to the brim so some water ...
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2k views

How is the water meniscus at the edge of a capillary tube

Suppose we have a capillary tube in which water can rise to a height of x cm. If we dip the tube such that the height above the surface is less than x, then how will the water meniscus be at the edge ...
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1answer
121 views

How plausible is a subsurface ocean on Pluto?

According to this article on physorg.com, it's likely that Pluto has a subsurface ocean of liquid water. It suggests that the ocean would be about 165 km deep, under an equally deep crust of solid ...
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Water under high pressure

If you were to sink a container to the bottom of a deep ocean and seal it there, then bring it up to the surface, would it retain its pressure? The answer for a gas is obviously yes, but what about ...
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1answer
384 views

How to simulate a crashing wave? [closed]

I'd like to create a very rough animation of a wave crashing on a beach. I'm guessing it would have to be a particle simulator, where you code in the forces between the particles and then integrate ...
7
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3answers
291 views

Why is concrete dry around cracks?

On a warm and partly cloudy day this summer, I was sitting in my office and suddenly heard rain on the roof. I went outside to shut my car windows. By the time I did that and was walking back into ...
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3answers
640 views

Why is salt so hard to remove from water?

Water molecules and various salt molecules are very different. However, it seems very difficult to separate the two. Once a salt is dissolved in water, an energy or chemical intensive method (like ...
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1answer
457 views

Electric Field Change Freezing Temperature of Water?

I assume that the reason water freezes is because as you decrease the temperature, the kinetic energy of the water molecules decreases and the dipole bonding potential eventually over comes the escape ...
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800 views

How does water carve rock?

How does water carve rock? And more generally, how does a soft material carve a hard material? Obviously it happens, but is it a continual process (every drop of soft water carries away a minute ...
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2answers
345 views

Patterns in laminar flow of tap water

This is a simple experiment that anyone can do at home. Open your tap so that the water maintains a laminar flow, and the cross section of flow is considerably thin. Place your finger 3-4 cm below the ...
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371 views

Polar ice deposits on the Moon - dispersed in permafrost loose rubble, or also massive/layered?

Water has been discovered on the Moon with remote sensing methods. Read the press release Diviner results indicate presence of widespread ice on the Moon on the "Diviner" infrared instrument on the ...
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Can a diver swim a short distance in great depths without being physically crushed by the pressure?

I recently saw "The Abyss". Does it make sense that they do dives in these depths (700m) with soft suits? Also - what is all the depressurization talk about? Why do divers need to depressurize long ...
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2answers
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How does the process of freezing water remove salt?

How does freezing water to make ice remove whatever salts were in the water to begin with?
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3answers
20k views

Can pockets of air exist underwater?

If yes, why don't they fill up with water, and can you breathe the air there? Like, it's not exactly atmosphere there, but an underwater cave with higher ceiling. P.S. Possible that it has a ...
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4answers
57k views

Freezing point of water with respect to pressure.

I know when the pressure is reduced, the boiling point of water is reduced as well. But how does the pressure affect the freezing point of water ? In a low pressure environment is the freezing point ...
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3answers
1k views

Why is steam used to spin turbines?

The ideal gas law tells us that the relationship between Pressure (P), Volume (V), Temprature (T), and quantity/amount (n) is $$ PV = nRT $$ where R is the gas constant. Say your an engineer who ...
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3answers
340 views

Is it faster underwater to go down without air or up with air?

So I had a very interesting conversation between me and my friends about this topic, but we could not find the answer. The Situation Lets say you are in a pool and you want to touch the bottom and ...
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2answers
671 views

Is it possible to disprove water memory with an entropy argument?

Water memory was a controversial experiment claiming to provide an explanation supporting homeopathy. The results were largely dismissed as being tainted by experimental error. One possible mechanism ...
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5answers
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Is there a depth at which a human body, with lungs full of air, will no longer float?

I was watching a special on divers who dove down hundreds of feet without tanks or gear. The show referred to a depth at which the diver was no longer buoyant and would actually sink, even with lungs ...
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1answer
167 views

Is nuclear fusion via underwater vacuum possible?

An under water explosion creates a bubbly which quickly collapses on itself. The action takes less that 1/100 of a second for bubbles less than a foot across. This creates a point of extremely ...
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2answers
997 views

If you stop water from expanding, will its temperature stop rising?

Water expands when it heats up. If you heat water in a container that prevents it from expanding, will its temperature top out -- maybe around the boiling point? And if not, will it still turn to ...
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1answer
235 views

Steam above meal

When I fry something on the pan and the fire is big and intensive (the flame over the pan), there is no stean above the pan or just a little. But when I turn off the fire, suddenly the steam appears, ...
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1answer
1k views

Does a domestic microwave work by emitting an electromagnetic wave at the same frequency as a OH bond in water?

I was told once that microwaves work by exciting water molecules in food. Also that this worked because the frequency in the microwave was the same as that in the bond between Oxygen and Hydrogen in ...
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1answer
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How the bond angle of a water molecule is measured?

How the angle of a water molecule is measured? The bond angle for water was first determined by vibrational and rotational analysis of its infrared absorption spectra. How is bond angle extracted?
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1answer
399 views

Water flushed down, water pumped up (in buildings)

I live in a tall building (20 floors) on a mountain. Because the water pressure from the water company is not enough, there is a water pump at the last floor which is activated each time someone is ...
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1answer
3k views

Why does blowing on someone who is wet feel colder than on someone who is dry?

The title says it all. If I'm standing in the wind and I'm wet, I feel much colder than when I'm dry. This is true no matter how warm or cold the water. Why is this?
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805 views

Microwave oven + water: dielectric heating or ion drag?

When you place a water or food in a microwave oven, it heats. Which process commits more energy to that: dielectric heating, or ion drag i.e. resistive heating? AFAIK, in distilled water (which is a ...
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1answer
2k views

How can I prevent drinking water from freezing in cold weather? [closed]

I'd like to keep a container of potable water in my car for when I get stuck, but in the winter it gets cold enough for bottled water to freeze. I can't put salt in it, because then it won't be ...
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1answer
11k views

Can a saltwater solution conduct electricity forever? [closed]

We know that very pure water does not conduct electricity, but salt water is a decent conductor. This is commonly explained by saying that "the ions carry the current through the solution", an ...
6
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1answer
12k views

Why does water sometimes form bubbles when I pour it into a glass?

Sometimes when I'm filling up a container with water from the tap, bubbles will form on the top of the water. They look a little like soap sud bubbles, but there's no soap suds present. I notice, ...
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3answers
7k views

Why does a bullet bounce off water?

It is known that bullets can ricochet off a body of water. Is surface tension responsible for this or is this the same behavior we see when an asteroid ricochets off the atmosphere? I don't think ...
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2answers
783 views

What does really attracts a water stream to a charged object?

I saw this video by Varitasium and I was not 100% sure about the third phenomena, a statically charged object attracting a stream of water, especially because he explicitly mentioned that it is not ...
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1answer
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Can you measure the speed of water coming out of a hose by its arc?

Water comes out of a horizontally stationed hose and creates an arc as it heads towards the ground. Can I determine the speed the water was traveling in when it exited the hose by the measuring the ...
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3answers
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What is the resonant frequency of liquid water?

I learned it's not 2.45 GHz. But what is it, then? In my failure to find the real value, I'm starting to wonder: does it even make sense talking about a resonant frequency of water molecules?
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2answers
137 views

Why does warm water sink?

It is well known that water at 4C is denser than water at 0C. This is the usual explanation for why a body of water freezes from the surface (also it's because ice is even less dense, but that's ...
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1answer
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Finding surface tension of water at certain temperature and pressure

The question is: Using the Young-Laplace Equation (if applicable), find the surface tension (dynes/cm) for water at 20 degrees Celsius with 2.5 psi. Round to the nearest tenth. ...
6
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1answer
872 views

What is highest water pressure at which electrolysis can be performed?

What is highest water pressure at which electrolysis can be performed to derive hydrogen and oxygen? Does the dielectric constant of water, which which lowers as pressure increases, have an effect on ...
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0answers
77 views

Can a submerged place in the sea have huge air pockets? [duplicate]

I know that air can be under water if there is something to contain it that prevents its escape. But can a place such as buildings or ancient ruins submerged totally under water hold air pockets as ...
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4answers
306 views

When displacement isn't possible

Stop me if i'm wrong but displacement is, for example, when you enter a bathtub the water level rises around you. What happens when displacement isnt possible? I'll give an example. I have two ...
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5answers
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Is it really possible for water to be held in a “cone shape” for a brief period of time?

I just saw this "trick" where a cup of water is turned over onto a table without spilling (using a piece of cardboard. After removing the cardboard from underneath the cup, the person then removes ...
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2answers
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What is the largest sphere of liquid water that could exist in space held together under it's own gravity? [duplicate]

What is the largest theoretical sphere of liquid water that could exist in space held together under it's own gravity? I've always wondered if a planet the size of earth could exist as a single volume ...
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2answers
480 views

How come a whistling kettle starts whistling only when water boils, and not long before - due to hot air escaping under pressure?

A whistling kettle will start to whistle when the water boils and turns into a jet of steam which then exits the small aperture in the spout. But why doesn't this happen much earlier - when the air ...
5
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3answers
256 views

Do hail stone fall down just when it is created?

Density of ice is much higher than air. Then how can hail stone remain in earth atmosphere before they fall down ?
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3answers
2k views

Is a water world possible, and for how long could it be stable?

I have several questions regarding this topic. First, could a water world be stable for thousands of years with most of its surface remaining covered in water. What would it take for this to be ...
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1answer
1k views

Does an ice cube change its core temperature as it melts?

Let's say we have an ice water solution in an ambience with room temperature, i.e. there is a permanent exchange of energy. Let's suppose the ice cubes were from the freezer, which is at $-18°C$. The ...
5
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4answers
2k views

Force of an impact on water

Today, at the Brazilian news, I heard that a men fell from a cruise into the sea, from a height of 50m, and decided to see if he could have survived. I took his weight for being 80kg. I did ...
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1answer
544 views

Distinctive properties of liquids

The molecules are closely arranged in solids, loosely arranged in liquids and are free to move in gases... But, Why are liquids (especially water) exhibiting these distinctive properties such as ...
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2answers
324 views

Wave with mass transport?

I don't think this question has been asked on this forum before (at least I didn't find it). In the case of a tsunami, an earthquake generates a wave which will travel with the sea/ocean as the ...
5
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4answers
6k views

Water in vacuum (or space) and temperature in space

So, water in vacuum will boil first and then freeze. I don't know how the freeze happens. As pressure lowers to zero, what happened to freezing point? (I know heat taken by vapor, and the water cool ...