# Tagged Questions

The process of a liquid changing into the solid phase

3answers
3k views

### 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?
0answers
30 views

### Hexagonal shape of snow flakes [duplicate]

As we know snowflakes has hexagonal shape. My question is why is that? and Is there any mathematical model which can explain that particular geometric shape of the snowflakes?
1answer
87 views

### 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 ...
3answers
171 views

### The float on a frozen lake

We have a bit of a debate going on at work. If a basketball (or any round float - let's assume one firm enough to not change size with temperature) was floating on a lake, and overnight the lake ...
0answers
22 views

### Is there a clever way to restrict the expansion of water in a partially filled barrel to the top?

I have an application for a cold room for a few weeks in late spring. If I freeze a partially filled barrel, typically it will initially freeze at the top, then freeze in. The result is bulge in the ...
1answer
184 views

### Why does thawing Coca-Cola generate force and expand the can as it thaws?

If I take a warm unopened aluminum can of Coca-Cola and place it in the freezer and let the Coca-Cola freeze solid, then take the can out of the freezer and let it thaw unopened in a typical room, the ...
1answer
423 views

### Why does hitting a cold bag of water freeze?

About 24 hours ago, I bought a box of 30 pieces water ice. I put them in the freezing compartment and when I came from work I was expecting a nice chilling ice. But when I opened the freezer, I saw ...
4answers
174 views

### What is the state of water at exactly 0°C?

Theoretically speaking, what is the state of water at bang on 0°C - not any lower or higher? Any lower would make it a solid whereas any higher would make it a liquid. But what about bang on 0°C? ...
0answers
58 views

### How water anomalies affects the Mpemba effect?

I understand basic explanation of Mpemba effect like this: Distant molecules are easier to realign into new formations. But if we compared two bottles of water like in Mpemba effect and one of them ...
1answer
293 views

### Can ice freeze? [closed]

We know that ice is already the frozen (solid) form of water. The question is more like: Can this frozen form freeze further? Or can it become more solid? (for example, by exposing to colder ...
1answer
321 views

### Meaning of chemical equilibrium between two phases

Suppose two phases 1 and 2 of water, say ice and water, are kept in a closed container, at a fixed temperature $T$ and fixed pressure $P$? Then I have the following question: Is phase 1 in ...
1answer
630 views

### Flakes of Ice in Frozen Milk and Orange Juice

When I was a kid, my family used to put our gallon jugs of milk and orange juice into the freezer when we'd go away on vacation so that they would keep longer. As I remember it, if we were gone for a ...
2answers
59 views

### why only surface of water get frozen in polar countries?

why only surface of water get frozen in polar countries? but if i kept glass full of water in fridge then not only surface, whole water turns frozen ,why?
0answers
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### Mixed-Alloy materials

Short version: Is it a physical problem (crystal structure/grains/redox/etc.) or just a logistics problem (keeping the solutes from homogenizing, molten/solid/temperature related problems) that keeps ...
4answers
2k views

### Why does water freeze from top to bottom

I was wondering why water freezes from up to bottom and not the other way around. The reason I question this is because in a Video I came across, I discovered water freezes from top but surely with ...
2answers
2k views

### Acer saccharum (Sugar Maple) Sap & Freezing

This may or may not be the appropriate scientific discipline to ask this question of, but I'll give it a shot. I'll happily invite chemists to chime in as well. It's time to tap sugar maples in the ...
7answers
9k views

### Why does ice form on bridges even if the temperature is above freezing?

So with this "arctic blast" continuing, I've noticed that for my area, the temperature drops below freezing just long enough to cause freezing rain, but then the sun comes out and the temperature ...
0answers
62 views

### Optimal temperature for Mpemba Effect

Is there an pptimal temperature for the Mpemba Effect? Is there an optimal initial water temperature for speedy freezing? If so, what is it? If a specific example is needed: There is a 100 milliliter ...
4answers
441 views

### 'Polar Vortex' Boiling Water to Snow is Mpemba Effect?

I am based far away from the icy storm currently blanketing the US - the 'polar vortex'. However, I have seen in the TV news footage of reporters throwing boiling water into the air, the water ...
0answers
667 views

### The formation of ice from water properties? [closed]

The formation of ice from water is accompanied by: A. absorption of energy as heat B. temperature increase C. decrease in volume D. an evolution of heat E. temperature ...
0answers
453 views

### What determines the rate at which an item will freeze in the given context?

Assume you have two pieces of meat in two rooms and all factors are constant e.g. meat volume, meat temp, room size and so on. The only difference is that the temp in one room is -5c and the other is ...
1answer
272 views

### Do ice crystals grow only as heat is being removed or also when an item is at a set temperature?

Chicken develops ice crystals between -2C to -4C. Now as chicken's temperature moves slowly from -2C to -4C ice crystals will grow. However, let's say that in a freezer, we set the final temp to -3C. ...
0answers
543 views

### Please clarify how freezer size and load affects rate of freezing

I was discussing how to make a freezer slow freeze food with somebody and asked them a question, they then gave me the below reply however I don't understand it properly. Can somebody please explain ...
1answer
309 views

### How does a freezer slow freeze food?

I have been told that the a freezer will freeze food slower if: a) the product load is greater then the capacity b) the capacity is greater then then the load. In a) I think this means if a freezer ...
3answers
2k views

### Melting and freezing point

Why is the melting and freezing point of a substance are always the same ? This was quoted in my textbook but they didn't give a reason for this being so. Thank you.
0answers
111 views

### How can I lower the temperature in my fridge compartment to become a high temp freezer?

I have a fridge compartment, the lowest temperature can be set to to about 0c. Is it possible I could bring it down to -2c, -3, -4 c etc by simply adding water bottles which were previously frozen in ...
1answer
157 views

### Why does water freeze at $0~^\circ\text{C}$ while poultry freezes at $-2.2~^\circ\text{C}$?

We all know the freezing point of water is $0~^\circ\text{C}$, however correct me if I'm wrong, but I believe the freezing point of poultry (which I'm guessing means water in poultry) is \$-2.2~^\circ\...
1answer
339 views

### 1/2 freeze a water bottle

Is it possible to quick freeze half of an unopened bottle of water or soda by putting half of the bottle in a subfreezing solution liquid nitrogen or other solution without freezing the whole bottle?
1answer
125 views

### How to homegrow large, momocrystalline water ice crystals

This is a follow up to this question:Can one get clear ice crystals from a dirty suspension?. How could one grow a large - meaning visible with the naked eye - water ice crstal with common household ...
0answers
104 views

### Can one get clear ice crystals from a dirty suspension?

Euteictic freeze crystallization is a method where an electrolytic solution is cooled and separated into a stream of (relativly) clean, pure ice and a salty brine. I know anectdotally of wine ...
1answer
152 views

### Electromagnetic field to cool a substance?

I saw somewhere that an electromagnetic field would cause a substance to let off thermal energy, ultimately resulting in the substance to cool really quickly. If this is possible, does the strength ...
5answers
71k 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 ...
1answer
441 views

### How does the size and load of a freezer affect the rate of freezing of an item?

I undertsand the size and load of a freezer can affect the rate a freezer will freeze food. I thought the temperature alone was the major factors which determined how fast/slow food freezes in ...
0answers
48 views

### How does a snowflake “know” to form symmetrically? [duplicate]

Possible Duplicate: Why are snowflakes symmetrical? Under ideal situations, a snowflake forms into near perfect hexagonal symmetry. How? For instance, when a water molecule moves towards the ...
3answers
4k views

### 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. ...
1answer
156 views

### Freeze and “break apart” an object. How?

Is it possible to freeze an object, say an apple, and then drop it so that is will break apart into pieces? And if so, how can it be achieved?
2answers
4k views

### Liquid with freezing point above 0 Celsius that could be use at ice rinks

Please help me with an answer to my dilemma: Is there a liquid that could be used to fill an ice rink (non-explosive, non-poisonous, etc), and have the freezing point above 0 Celsius?
2answers
1k views

### Why laundry dry up also in cold/frost?

Why laundry dry up also in cold/frost? When you have frost, water in the clothes should freeze, but if clothes are dry, then it should be possible that steam in the clothes does not have time to ...
1answer
14k views

### What happens to the temperature of the water when you add salt to a bowl of melting ice?

If you have a bowl of ice that's melting, so the ambient temperature is just above 0 °C, what happens to the temperature of the water when you add salt? I know that the freezing point of salt water ...
1answer
177 views

### can hydrogen stay frozen in vacuum?

I've look into the hydrogen state diagram, and it seems that it can be frozen under pressure. Question: Does this mean that hydrogen cannot be kept frozen in a vacuum chamber?
4answers
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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 ...
1answer
692 views

### Cause of sea ice freezing during an upwell event

One of the Episodes of BBC's documentary Frozen Planet describes an upwell phenomenon in the Antarctic Ocean. I am trying to understand the cause of seawater freezing when this upwell occurs. Liquid ...
3answers
11k views

### 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, ...
4answers
18k views

### What kinds of materials contract the most in cold temperatures?

I know that water expands in the freezer, but I'm curious about which materials contract in response to cold temperatures --- and most importantly, which ones undergo the most drastic changes?
4answers
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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 ...
0answers
2k views

### Easy to obtain liquid with freezing point a couple of degrees above 0 Celsius [closed]

Please advice me a liquid whose freezing point is 2-5 Celsius. I know that the solution of salt in water can have freezing point of about -3 Celsius. I would like to know if similar liquid but with ...
3answers
880 views

### Will the water added to an ice piece freeze?

Water, at room temperature is poured into a hole made of a block of melting ice(kept at room temperature).I was wondering if the water will ever freeze? Thank you.
4answers
5k views

### 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 ...
3answers
5k views

### 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 (...
4answers
9k views

### Dangers of using liquid nitrogen

So, I remember in college physics the prof using liquid nitrogen in a demonstration. When he was done, he threw the container of LN at the front row, and of course it evaporated (or whatever) before ...