# Tagged Questions

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### Being in a solid state, why is ice slippery? [duplicate]

Saying that ice is slippery is like saying that water is wet -- it's something we've known for as long as we can be said to have known anything. Presumably, humans as a species knew ice was slippery ...
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### Why does ice melting not change the water level in a container?

I have read the explanation for this in several textbooks, but I am struggling to understand it via Archimedes' principle. If someone can clarify with a diagram or something so I can understand or a ...
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### Why is ice made from boiled water clear?

A common trick to make clear water ice is to boil pure water prior to freezing it. Why does that work and what are the white inclusions in ice that was made from unboiled tap water?
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### Why does water rise through a hole in ice

I've just been watching a doco where some guys cut a hole in a frozen lake, the ice is 3 feet thick, I was surprised that the water rose to the level of the ice. My friend assures me it's because ...
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### Are bubbles in ice at a lower or higher pressure than atmospheric pressure?

When water phase-transitions into ice it expands. The water usually contains dissolved air. Freezing forces the air out of the solution into bubbles. Are these bubbles at a lower or higher pressure ...
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### Ice skating, how does it really work?

Okay, some textbooks I came across, and a homework assignment I had to do several years ago, suggested that the reason we can skate on ice is the peculiar $p(T)$-curve of the ice-water boundary. The ...
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### What is the status of Mpemba effect investigations?

There is this puzzling thing that is called Mpemba effect: paradoxically, warm (35°C) water freezes faster than cold (5°C) water. As a physisist, I've been asked about it several times already. And I ...
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### Why are snowflakes symmetrical?

The title says it all. Why are snowflakes symmetrical in shape and not a mush of ice? Is it a property of water freezing or what? Does anyone care to explain it to me? I'm intrigued by this and ...
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### Ice cube left in water at 0 °C for a thousand years

Let's say we take an ideal calorimeter with a liter of water at +5 °C and throw a 5×5×5 cm cube of ice having temperature of –70 °C. I choose these initial parameters so that the stationary ...
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### Thermodynamics of supercooled water

Now that it's been freezing outside for the last few days, I experimented a bit with supercooling. I've left a bottle of clean water outside for a few hours, and behold, when I shook the bottle, the ...
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### Do all phases of ice look the same visually?

I recently read about different phases of ice on Wikipedia. But I can't find any pictures of the different ice phases. Do they all look alike visually? If you weren't able to measure the pressure and ...
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### Why does ice have a lower density than water?

Can someone explain me why is ice less dense than water? As I know, all solids are usually denser than the liquids (correct me if I am wrong).
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### Why do crystals grow in preferred directions?

I want to know why snowflakes (and other crystals) grow symmetrically and I find the leading answer to the established question to be entirely unsatisfactory. When water freezes, you get ice. Ice,...
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### How fast does an ice cube melt in a microwave?

I have noticed that when I microwave an ice cube it appears to melt more slowly than I would expect. For example, an equal volume of water starting at 0 deg C would probably be at boiling point before ...
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### How do ice spikes form?

I recently saw this picture posted on Twitter which shows a so-called ice spike rising from an ice cube tray. I have read the Wikipedia page, but it doesn't mean much to me. My instinct was that it ...
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### Is there a temperature at which ice is denser than water?

Normally ice would float on water because its density is less compared to that of water as a liquid. But is it possible that its density will increase due to a very low temperature or is ice in any ...
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### Why is ice more reflective than liquid water?

Why is ice more reflective (has higher albedo) than liquid water? They're both the same substance (water). Is something quantum mechanical involved?
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### Why does soda fizz when it meets ice?

I read that the soda's temperature allows it to contain its $\text{CO}_2$: colder means it can retain its bubbles better. So, why does soda fizz when it meets ice? If anything, because the soda is ...
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### Why did my frozen water bottle explode when I opened it after it defrosted a bit?

Last night I filled a 20 fl oz bottle (http://www.thenibble.com/reviews/main/beverages/soft-drinks/boylans-mash.asp) with lukewarm water from my tap. I filled the bottle pretty much to the brim, ...
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### Thoughts on the ice cube from orbit problem

Let's say we have a really exquisite cocktail party somewhere in New Mexico, and we just ran out of ice cubes. To the rescue comes this new service provided by Orbital Glacier Inc. They provide ice ...
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### Can you make ice red hot?

This video clip allegedly shows an otherwise unspecified ice cube that turns red hot (and burns) due to induction heating. Can somebody explain how this works?
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### Does water turn solid under deep ocean because of high pressure?

I know that we can make water solid with high pressure, so I think water will be solid in the deep ocean? If that is true, the depth of the ocean would be limited because water will become ice? ...
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### How wide does a wall of ice need to be to stay in place?

Let us say that we have unlimited manpower to construct a huge wall of water ice e.g. 200 m tall (700 feet). -and that the wall is placed in a climate, where the temperature never (for your purpose) ...
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### Frost bubble formation

I woke up recently to find the following structures on my lawn; they resemble bubbles, but are formed from ice (we had a moderate frost overnight). There were eight of these 'bubbles' on my lawn and ...
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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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### Ice bath is always 3C, why?

I've always learned that a mixture of ice and water should reach equilibrium at approximately 0C. I've actually tried to create that a number of times in different contexts and always fail. First, ...
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### Water level of ice in cup [duplicate]

Since ice is less dense than water, it floats on it, we all know this. Now suppose, if ice is floating in a glass cup, when the ice melts there should be some change at water level in the glass cup. ...
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### Why is it easier to glide on sharp ice skates than on dull skates?

There have been previous questions (e.g. here and here) on Physics.SE about the mechanism that makes ice skating possible. Reviewing these, as well external references, it seems pretty clear that the ...
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### Why can we skate on ice? [duplicate]

I have known the reason why skate can slide over ice is that water's melting curve in terms of pressure and temperature has a negative slope. If the pressure due to our mass increases sufficiently ...
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### Why does an ice cube not twirl along when twirling a drink glass?

When you have a drink with an ice cube and twirl the glass, the liquid itself seems to twirl but the ice cube stays roughly in the same place. Why is this?
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### Melting ice: reversible or irreversible?

I am looking into whether the melting of ice (or any substance for that matter) at constant pressure and temperature is reversible or irreversible. Different sources say different things, and it may ...
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### 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 ...
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### Why did my liquid soda freeze once I pulled it out of the fridge and opened it?

This isn't a duplicate to "Why did my liquid soda freeze once I pulled it out of the fridge?". My question is why soda froze after it was opened. Opening a can or bottle seems to have a larger effect ...
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### Why isn't ice a good electrical conductor?

Water can conduct electricity, and some solids can conduct. Why can't ice? Are ice molecules too packed together to let valence shell electrons bounce across each other to create electrical charge? ...
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### Would dropping large blocks of ice into the ocean mitigate global warming?

This amusing Futurama sketch 'solves' global warming by dropping increasingly larger blocks of ice into the ocean. Presumably the blocks of ice are harvested from a different planet. Would this ...
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### what cools bottle of water faster: ice or snow

Imagine you have a pile of snow and a pile of ice shards. You put a soda bottle which has a room temperature into both piles. Which bottle is going to cool down faster?
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### Why do ice cubes make a cracking sound when placed in fizzy wine (Prosecco)?

When placing ice cubes in a fizzy drink such as Prosecco, ice makes a cracking sound, after which the fizzy bubbles more than usual. What is the physics of this phenomenon?
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### Does wax go through a sharp phase transition when it melts?

When ice melts, the system goes sharply from being solid to being liquid. There is no intermediate state where it is soft. This is a true phase transition. The thermodynamic potential is not an ...
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### Why does ice become sticky the colder it gets? [duplicate]

I noticed that ice becomes stickier the colder it gets. I am reminded of the fool who stuck his tongue to a cold galvanized steel pole and got stuck to it. I am guessing that the pole was so cold that ...
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### Why is ice less dense than water?

The answers to this question explain that ice is less dense than water because it has a "crystal structure", but they dont explain what exactly that is and why this happens, also I saw this answer ...
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### Why would a layer of ice prevent frost damage to fruit?

I know a family that grows fruit such as blueberries in a climate that frosts on occasion. When this happens, they turn on sprinklers which covers the buds and fruit with a layer of water which turns ...
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### Why do my ice cubes stick together? [duplicate]

When I put ice cubes in a glass of water, I find that sometimes they will stick together and form a sort of "bridge" between them as they melt. There is usually a visible line where one ends and the ...
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### Freezing point depression - cooling my drink with the same method as salt on a highway?

I understand that adding/sprinkling, say NaCl, on a highway depresses the freezing point by making any moisture on the road harder to freeze as the NaCl molecules get in the way of phase transition. ...
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### Do sodium chloride(ions) melt the ice or not?

My question is this, In European countries, they use NaCl or KCl to melt ice during the winter season. In Asian Countries, they use NaCl to keep the ice without melting. (Ex- Ice cream boxes, Beer ...
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### Air bubbles in Ice and cause for their shape?

I was looking at the ice formed in my refrigerator and found out there were a lot of air bubbles inside it. The shape of the air pockets seemed strange to me. There were many small spherical ones ...
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### Can ice thickness be different on two nearby lakes?

In winter, is it possible for two distinct bodies of water, which are a few kilometers apart (so they are exposed to roughly same temperature), to have different thickness of ice? Does the area of the ...
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### Where are the ice rings in X-ray crystallography located?

I threw this image of one of my protein crystal's diffraction pattern (not the greatest) on a poster, and was wondering where (what reciprocal dimension) the ice rings are located as it might be a ...
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### Why is there ice at the Earth's poles? [duplicate]

I beg your pardon for such a silly question, but I've never really understood the explanation they gave in the Geography textbooks. If the slanting Sun's rays due to the Earth's axial tilt can cause ...
It's my understanding that the colder liquids get (or anything else for that matter) the slower the constituting particles move. That being the case, why is H$_2$O either 'water' or 'ice'? Given that ...