How Ice Melts

Killer Instinct writes "Ever wonder how ice melts? Until now, scientists could not explain why ice cubes in your drink melt. They've known the basics, but the details remained elusive. A breakthrough new study, announced yesterday, supports a leading theory that melting starts when the fundamental structure of matter begins to crack. Melting is considered a basic phenomenon in physics. An understanding of how it works is crucial to gaining a firm grasp on the physical world."

Comments

Hmmmmm...

[chriswaclawik]

Ever wonder how ice melts?

No.

Re:Hmmmmm...

[turtled]

I didn't read the full article earlier, was this one of the top 125 Big Science questions?

Re:Hmmmmm...

[poopdeville]

That's a shame. This is a very interesting topic. We've known for centuries that melting is related to heat, and there are molecular models of freezing. Namely, water molecules tend to align themselves in a crystalline structure unless they're stirred up. A region freezes when the average kinetic energy is low enough for the molecules to align themselves. Consider a fairly large volume of water -- in macroscopic scales. Heat conduction through liquid water is faster than through ice, because of convection. So the macroscopic freezing process isn't reversible. (There are other reasons why the process isn't reversible, but one suffices)

This means that a different process is responsible for macroscopic melting. Since macroscopic chunks of ice tend to be imperfect crystals, it stands to reason that the weak unions between crystalline structures facillitate melting.

Re:Hmmmmm...

[poopdeville]

This could have all sorts of ramifications in materials science. If a good model for macroscopic melting is found, we might be able to design processes to alloy metals much more resistant to heat than are currently possible, for instance.

Re:Hmmmmm...

[mizhi]

An understanding of how it works is crucial to gaining a firm grasp on the physical world.

Really? I don't really understand it and I seem to be able to grasp objects just fine.

Re:Hmmmmm...

[Loie]

Next week on Slashdot, scientists will discover exactly how grass grows, how paint dries, and how flies fuck!

Re:Hmmmmm...

[nystire]

What is between your (partner's|) legs doesn't quite count here...

OT: How does one write a lambda in HTML? :)

Re:Hmmmmm...

[afa]

Well, in fact, I am more interested on how crystals solve into solutions....

Re:Hmmmmm...

[moonbender]

Simple: λ - not on Slashdot, though.

Re:Hmmmmm...

[eaolson]

Nope, freezing and melting are both entirely reversible processes, in the thermodynamic sense. For them to not be reversible, there would have to be an increase in entropy somewhere.

And it's the same "process" involved. The biggest difference between melting and freezing is that freezing requires the nucleation of a crystal, which is a time-dependent process. Melting can generally occur without it.

Re:Hmmmmm...

[swillden]

Really? I don't really understand it and I seem to be able to grasp objects just fine.

I laughed, but then thought about this a little more. Yes, you do understand it.

You understand the pull of gravity, you understand friction and its relationship with force, you understand leverage and you understand that excessive force can crush objects. Even if you can't describe the concepts in detail, mathematically, you must understand them in order to be able to grasp, hold, pick up, move, etc., objects.

Understanding how ice melts is just a much more sophisticated version of understanding how to close your fingers to pick up a baby rattle.

Re:Hmmmmm...

[Atraxen]

Actually, explaining various behaviors of water is one of the hardest problems remaining in science. Water is less dense when frozen (ice floats) but this is the opposite of most solid/liquid pairs. Water has a 'critical point' at 4C, where its density is at a maximum (even more impressive is that it has a density maximum and minimum within 4C!) If you remember chemistry, you always treated acids as making H+, or maybe they were more rigorous and wrote H3O+. In actuallity, we don't know how many water molucles are surrounding the H+ from the acid - I've seen papers that strongly suggest 13, and others suggesting more and less. Because of its small size, water molcules exchange very quickly - I can't recall the exact value this early on a Saturday, but if a particular water molecule stays around an object for more than a nanosecond, it would be the first time - waters exchange on the order of femtosconds (10^-12 s). Large dipole, small molecule, hydrogen bonding, big symmetry - all this makes water one heck of a wierd special case.

Re:Hmmmmm...

[russellh]

Really? I don't really understand it and I seem to be able to grasp objects just fine.

wow, quite a skill to grasp melting objects.

Re:Hmmmmm...

[Punk Walrus]

Boasting about the opposable thumbs again, aren't you?

Re:Hmmmmm...

[ShortBeard]

This makes me think of TMBG's "Why Does the Sun Shines".

If there's a song of this ice melting I may learn something yet.

Re:Hmmmmm...

[cpugeniusmv]

I believe it was the forty-second one.

Re:Hmmmmm...

[king-manic]

wow, quite a skill to grasp melting objects.

It is, pyrokinesis is great. I never need a lighter, and my enemies don't last long. Hell campign is great fun, and just a touch of it on a attractive woman leads to many revealing scenes.

Re:Hmmmmm...

[ratnerstar]

Yes, and now scientists are working on the "How Does Paint Dry?" and "How Does Grass Grow?" questions. What a wondrous age we live in!

Re:Hmmmmm...

[poopdeville]

I meant something stronger than mere thermodynamic reversibility. There are many ways for water to freeze and ice to melt, and as long as the end results are the same, they're thermodynamically equivalent. The research presented here examines the reasons why one path is chosen over another. Instead of dealing with statistics, the researches are investigating particulars.

Re:Hmmmmm...

[Anonymous Coward]

Forget about alloys ... just imagine non-melting ice!

freezing water

[pintomp3]

using hot water makes it faster than using cold water, right? at least that's what countless ppl believe despite explanations otherwise.

Re:freezing water

[X1011]

Not hot, boiling.

Re:freezing water

[takeya]

makes sense that using hot water makes it melt faster. the sink at work only has warm/hot water (for washing your hands) but I will put ice in a cup and and get water from it, usually the ice melts quickly, until the water cools, then starts melting slower and slower. In cool water from a tap or cold water/drinks from a fridge, ice can stay intact much longer.

Just an observation.

Re:freezing water

[guardiangod]

It depends on the fluid's temperature....

Source

Dear Cecil:

I have a friend who insists that filling an ice cube tray with warm water will cause the cubes to form more quickly than they would if you started with cold water. He said it had something to do with the air circulation around the trays being affected by the temperature.

Not knowing much about frigidity myself, but being contrary, not to mention skeptical, by nature, I expressed doubt. Cecil, was I right, or is there indeed some basis in fact for this foolishness? --Mary M.Q.C., Santa Barbarba, California

Cecil replies:

You were smart to let me handle this, Mary. God knows what would happen if you tried to experiment with ice cubes on your own.

Needless to say, I conducted my research in the calm and systematic manner that has long been the trademark of Straight Dope Labs. First, I finished off a half a pint of Haagen-Dazs I found in the fridge, in order to keep my brain supplied with vital nutrients.

Then I carefully measured a whole passel of water into the Straight Dope tea kettle and boiled it for about five minutes. This was so I could compare the freezing rate of boiled H20 with that of regular hot water from the tap. (Somehow I had the idea that water that had been boiled would freeze faster.)

Finally I put equal quantities of each type into trays in the freezer, checked the temp (125 degrees Fahrenheit all around), and sat back to wait, timing the process with my brand new Swatch watch, whose precision and smart styling have made it the number one choice of scientists the world over.

I subsequently did the same with two trays of cold water, which had been chilled down to a starting temperature of 38 degrees.

The results? The cold water froze about 10 or 15 minutes faster than the hot water, and there was no detectable difference between the boiled water and the other kind. Another old wives' tale thus emphatically bites the dust. Science marches on.

AN ANOMALOUS SITUATION ARISES

Dear Cecil:

Just a few days after I read your column on whether hot water freezes faster than cold water (you said it didn't), I happened to come across an article in Scientific American entitled "Hot Water Freezes Faster Than Cold Water. Why Does It Do So?" What gives? I hope we will see another column soon resolving the issue. --Ellen C., Chicago

Dear Ellen:

I know it must unnerve you to find that a supposedly infallible source of wisdom can make mistakes, so let me hasten to reassure you: Scientific American did not screw up. My results and theirs (specifically, those of Jearl Walker, author of SA's "Amateur Scientist" column) are consistent--we were just working in different temperature ranges.

I found that cold water (38 degrees Fahrenheit) froze faster than hot water out of the tap (125 degrees F). I chose these two temperatures because (1) they were pretty much what the average amateur ice-cube maker would have readily available and (2) I couldn't find a mercury thermometer that went higher than 125 degrees.

Jearl, who is not afflicted with penny-pinching editors like some of the rest of us, was able to get his mitts on a thermocouple that could measure as high as the boiling point, 212 degrees F. He found that water heated to, say, 195 degrees would freeze three to ten minutes faster than water at 140-175 degrees. (There were differences depending on how much water was used, where the thermocouple was placed, and so on.)

Jearl suggested that the most likely explanation for this was evaporation: when water cools down from near boiling to the freezing point, as much as 16 percent evaporates away, compared to 7 percent for water at 160 degrees. The smaller the amount of water, of course, the faster it freezes.

In addition, the water vapor carries away a certain amount of heat. To test this theory

Re:freezing water

[Escherial]

This is a particularly pervasive myth. Of course, the folklore is incorrect: according to basic thermodynamics, a quantity of warm water will invariably take longer to freeze than an equal quantity of cold water.

Note that key phrase, "an equal quantity" -- in an experiment with two uncovered containers of hot and cold water, you'll find that the resultant mass of water in each of the containers is anything but: a good deal of water from the hot water container is lost to evaporation. So, with a decreased mass, it's easy for the originally hot water to cool more quickly than a significantly larger mass of cold water.

Essentially, hot water does cool faster than cold water in an uncovered container, but you end up with significantly less ice than if it were originally cold.

Re:freezing water

[Anonymous Coward]

This is always misunderstood. It's not hot water - It's distilled water (probably due to mistaking boiling for boiled). An equal volume of distilled water will freeze faster than tap water.

Re:freezing water

[clockmaker]

Actually, I always heard that you make ice with warm water to make crystal-clear ice that looks better for parties, etc. (no white in it). I never heard that it froze faster.

Re:freezing water

[the_mystic_on_slack]

No, in fact they are talking about boiling water; a.k.a. 100 degrees Celsius. As people have pointed out, there are two reasons. Evaporation is a cooling process (that's why you sweat), and during evaporation liquid mass takes a gas form, thus there is less of your ice cube to freeze. And distilled water doesn't freeze "faster" it freezes at a higher temperature than water with impurities. Hence, people in the north applying salt to their streets.

Re:freezing water

[tijnbraun]

It is called the Mpemba Effect.

More on this phenomenon (history en possible explanations) here

Re:freezing water

[magarity]

using hot water makes it faster than using cold water, right?

Water that's really hot will loose heat more rapidly than cool water in the same surroundings. What people don't get is that once the hot water has cooled off, it now cools at the slower rate.

What actually IS useful about freezing hot water is that there are a lot less air bubbles so the ice doesn't crack and throw shards out when you pour freshly brewed tea over it on a hot summer afternoon.

Re:freezing water

[Serpentine]

It is not a myth although it certainly is pervasive...among physical chemists. Basic thermodynamics is just that: basic. Like all laws of science it makes assumptions that are not always true. Under specific conditions the effect can still be observed once evaporative loss is compensated for; it apparently has even been observed in closed containers.

IIRC, the explanation for the ice-cube-trays-in the-freezer 'anomaly' seems to involve the specific temperatures of the two samples, the insulating sides of the tray (minimising heat loss via conduction), enthalpy of vaporisation and the temperature gradient in the water. But don't quote me.

What appears to be a comprehensive exposition on the matter can be found here here.

Re:freezing water

[red990033]

Maybe not hot water, but certainly boiled tap water. There are a number of additives in tap water, Chlorine and Flouride for example. There can be any number of "extra" ingredients. When boiled, most (probably not all), will evaporate away (assuming there is no lid on the pot).

Flouride has a freezing point of -137C, and Chlorine has a freezing point of -100C. Obviously we all know 0C is the freezing point for H2O.

I'd be willing to bet that if you took all the extra stuff you find in tap water, look up their freezing points, you'll find most of them are far colder than H2O.

Yea, it's only a small amount of extra stuff, but it adds up quickly.

Re:freezing water

[Adult film producer]

Someone else can explain the science behind it, I'm certainly not qualified but I've tried this experiment three times and each time it's been the same. The cubes made with hot water generally 'form' faster but the core is not as solid as the cubes made from cold water, that were completely solid at the time of measurement.

Re:freezing water

[deathguppie]

This is odd, I remember hearing this thing about hot water freezing faster when I tried to take hot water out to my horse, when I was a kid. (no I'm not kidding, I had a horse.) My father told me that the water would freeze faster if it was hot, but I didn't believe him. I have never tried this with a refrigerator, but I have to admit in this situation he was right. I timed it several times and came to the same conclusion.

This was the theory I came up with then. (please rate this 1:unplausable)
100 deg cel | |
80 deg cel |bucket 1| (diff between b1 and end 80 deg between b1 & b2 40 deg)
60 deg cel | |
40 deg cel |bucket 2| (diff between b2 and end 20 deg)
20 deg cel | |
0 deg cel |end temp|
-20 deg cel | |
-40 deg cel | |
-60 deg cel | |

the resulting difference being the same as if bucket 1 was at 20 deg cel moving to -20 cel meaning that bucket 1 would reach temp 0 cel at half the time

Re:freezing water

[tek.net-ium]

This is a particularly pervasive myth. Of course, the folklore is incorrect: according to basic thermodynamics, a quantity of warm water will invariably take longer to freeze than an equal quantity of cold water.

I hate to nitpick, but thermodynamics will not tell you that. The heat transfer details depend on the nature of the system, which is outside the scope of thermodynamics.

You could imagine two closed cylindrical containers, each initially filled with a substance in a liquid state. The liquid of container A is at a temperature such that the density is the minumum. The liquid in container B is initially at a higher temperature than container A. For simplicity's sake, the only extremum of density with respect to temperature is the minimum I mentioned. You begin cooling both liquids at the top of the cylinder.

As heat is transferred from container A, the density will always be increasing from the top to the bottom of the container in a predictable fashion, i.e., the "heavier" substances will always be on the bottom of the container. This doesn't promote convection. With container B, there are good opportunities for convection, due to the varying density gradient and the effect of gravity. Solid forming on the top of container B could even sink. The convection leads to a higher sustained temperature gradient at the cylinder boundary, leading to faster heat transfer and faster cooling.

Note that this mechanism doesn't require an open system. There are, of course, other possible mechanisms, but this is the simplest one I could come up with.

Re:freezing water

[Anonymous Coward]

except if you're using tap water, the hot may freeze faster but people say it's cleaner since it hasnt been sitting in the water heater :)

Re:freezing water

[Anonymous Coward]

meaning that bucket 1 would reach temp 0 cel at half the time

Unless you measured and timed the temperatures of both buckets from start all the way to freezing temperature, you really haven't really timed it..

One should expect a substance will tend to change in temperature faster, the farther it is from the temperature of the environment, and indeed in proportion to that difference, except where the material actually changes states between solid/gas/liquid/etc, the change of temperature is expected to be be a fairly continuous thing predictable thing: if you have an approximation the proper coefficient for the substance, then how long it will take to cool is expected to be fairly predictable, and having a greater temperature normally means it will cool quicker at first and slower later (in the long run, taking longer).

Hot water has to become cold water before it can freeze. It won't "skip temperatures", it will eventually pass through the same temperature your cool water was at.

But 100 degrees is special, because it is water's boiling point, and you ought have tried with hot water that was not boiling so that you could be consistent about the volume of fluid you are working with, without having big portions of the hot water evaporate: it makes a difference how quickly it freezes whether you heat a gallon of water or heat water and then pour out a gallon. (Of course the amount of material matters also)

The temperature of the container matters. Depending on the substance, whether it is a good insulator or not and if it's covered would effect the rate at which the water freezes.

Water needs to be measured out in equal amounts before heating for results to be comparable, since for all you know, water might change density when you heat it.

Depending on how cold it is outside, the difference between hot water and cold water is possibly quite tiny compared to the difference in energy between cold water and frozen water.

One of your buckets could have simply frozen first out of pure luck or small factors other than its starting temperature, or because it was so enormously cold outside that the buckets' difference in temperature was insignificant and less important than the position and direction of the wind with respect to the bucket, for example.

Re:freezing water

[MPHellwig]

Well my logic indicates that this phenomena occurs when the thermo dynamics takes place in a closed and small environment.

Thus my theory:
"If any matter is in a state where it can enrich its environment with its own or others matter, the environment will be more capable to equalize the energy difference between the matter and the environment then it could before the enrichment."

In this case hot water makes the air in the freezer more humidit, therefor conducting more heat thus cooling down faster.
When the freezer is opened the humidit air escapes and leaves scientist clueless why the water froze faster then calculated.

How to test this logic:
- Take 2 identical relative small containers.
- Have access to a freeze room (as big as there is) and a freeze box.
- Make sure they are the same temperature and have the same freezing curve, meaning the small box has relative more freezing power (aaah!).
- Boil some water, vodka, juice whatever you like.
- Put the exact amount in each container and put one container in the middle and center of the room and one in the middle and center of the box.
- Measure which one is the first to be solid.

If my theory is correct the container in the small box would solid faster because the environment in the small box has relative more energy transfer potential then the one of the big room.
Because the small box has relative more cooling power (most small freezer do) it can use the potential higher energy transfer to cool down the matter faster.

This theory doesn't apply when the matter can not enrich the environment with its own matter enough to create more energy transfer potential, be it that the amount of matter is to small or the environment is too big and even when the first is met, the cooling equipment must be powerful enough to use the potential.

Now taken this true, we can follow the logic that when the conditions are met, it is potential possible that the temperature difference between hot and warm water is countered by the higher energy transfer capacity of the air, thus resulting that the "warmer" water freezes at the same time or earlier then the "colder" water.

The M.P.Hellwig theory to explain the Mpemba effect, now say that five time fast after each other :-)

Re:freezing water

[tootlemonde]

Thus my theory

Your theory is more properly a hypothesis:

Hypothesis: This is an educated guess based upon observation. It is a rational explanation of a single event or phenomenon based upon what is observed, but which has not been proved. Most hypotheses can be supported or refuted by experimentation or continued observation.

A theory is an explanation of a set of related observations or events based upon proven hypotheses and verified multiple times by detached groups of researchers. One scientist cannot create a theory; he can only create a hypothesis.

Thus the "Hellwig hypothesis". Nice alliteration as well.

Re:freezing water

[MPHellwig]

"but which has not been proved"

Now that is a hypothesis, my theory has been proven a dozen of times in restaurants kitchens.

Re:freezing water

[Lord Crc]

This is a particularly pervasive myth. Of course, the folklore is incorrect: according to basic thermodynamics, a quantity of warm water will invariably take longer to freeze than an equal quantity of cold water.

It seems it's not a myth after all, and has a name: the Mpemba effect.

It seems that under certain conditions, hot water can indeed freeze faster than cool water. Just why and how exactly this happens seems be under discussion though, and might be a combination of a variety of factors, including:

• Evaporation could reduce the volume to be frozen
• Cold water can contain more disolved gasses, which can alter the freezing point and the ability to form convection currents
• Hot water will form convection currents faster, which aids in the cooling process

Re:freezing water

[poor_boi]

Now that is a hypothesis, my theory has been proven a dozen of times in restaurants kitchens. A theory that has been proved is a law.

But your hypothesis deals with varying the efficiency of the cooling mechanism, not differences in behavior between hot and cool liquid undergoing treatment from indentical cooling mechanisms, which is what measure Mpemba effect calls for.

Re:freezing water

[tootlemonde]

my theory has been proven a dozen of times in restaurants kitchens

But not necessarily by "a detached groups of researchers."

However, with difficulty new PhDs have in finding employment in their fields, restaurant workers may be well be qualified to test theories. They could publish their findings in "The Golden Arches Journal of Kitchen Thermodynamics".

Re:freezing water

[MPHellwig]

Well thats the point I think that Mpemba effect is indeed nothing else then an influence in the identical cooling mechanism.

Otherwise it would work too when you have 2 _sealed_ container of water the one being 160 and the other 120 degrees celsius, that the 160 one will be the quickest to room temperature in a open environment.

Re:freezing water

[MPHellwig]

As long as the PhD don't doo the cooking, fine with me. :-)

Re:freezing water

[Anonymous Coward]

This conclusion, however, is not borne out by actual experiments. From the article linked above:

One explanation of the effect is that as the hot water cools, it loses mass to evaporation. With less mass, the liquid has to lose less heat to cool, and so it cools faster. With this explanation, the hot water freezes first, but only because there's less of it to freeze. Calculations done by Kell in 1969 [11] showed that if the water cooled solely by evaporation, and maintained a uniform temperature, the warmer water would freeze before the cooler water.

This explanation is solid, intuitive, and undoubtedly contributes to the Mpemba effect in most physical situations. However, many people have incorrectly assumed that it is therefore "the" explanation for the Mpemba effect. That is, they assume that the only reason hot water can freeze faster than cold is because of evaporation, and that all experimental results can be explained by the calculations in Kell's article. However, the experiments currently do not bear out this belief. While experiments show evaporation to be important [13], they do not show that it is the only mechanism behind the Mpemba effect. A number of experimenters have argued that evaporation alone is insufficient to explain their results [5,9,12] -- in particular, the original experiment by Mpemba and Osborne measured the mass lost to evaporation, and found it substantially less that the amount predicted by Kell's calculations [5,9]. And most convincingly, an experiment by Wojciechowski observed the Mpemba effect in a closed container, where no mass was lost to evaporation.

Re:freezing water

[jeddak]

> Not knowing much about frigidity myself, but
> being contrary, not to mention skeptical, by
> nature, I expressed doubt...

I know all about frigidity. Just ask my wife.

Re:freezing water

[Dread Pirate Shanks]

My old college roommate, a hockey player and zamboni driver, was also under the very distinct impression that the reason the water in zambonis was heated was because it froze faster on the surface. Despite whatever reason I could provide, including the fact that the water can't be allowed to freeze in the machine and the fact that hot water will melt away imperfections on the ice, he still insisted that the sole reason it was warmed was so it would freeze faster. He then looked it up on the first zamboni site Google turned up, and they too claimed it would freeze faster.

Tell you what, that's the last time I'll EVER question a hockey player in matters of science again!

Re:freezing water

[dtungsten]

I think that when water pipes freeze, it is usually the hot water pipes that freeze first. This was certainly the case in my dad's house. Though there may be another explanation to it (like maybe the hot pipe was thinner); the explanation I was given was that the freezing temperature of the hot was higher that that of the cold due to having less things dissolved in it, in the same way that salt "melts" ice.

Ice melts when you

[The_Fire_Horse]

jam it up your ASS !!!

This kind of research...

[Anonymous Coward]

melts me up.

Anti-Cold

[TimeTraveler1884]

Ever wonder how ice melts?

Not really. But I have a hypothesis that it has something to do with heat or as I call it, "anti-cold." There seems to be a relationship between 0 degrees Celsius and ice melting. Likewise a relationship with 100 degrees Celsius and water boiling (when under one atmosphere of pressure). There must be some underlying mathematical connection; for these events and their temperatures surely can not be coincidence. Some day I will solve this mystery, but only when I am properly funded by government grants.

Re:Anti-Cold

[guardiangod]

That's because Celsius was defined with water in mind.


The Celsius temperature scale was designed so that the freezing point of water is 0 degrees, and the boiling point is 100 degrees at standard atmospheric pressure.

So yah, there is a relationship- ( x1 - x2 )/ 100 :)

Unless, of course, this is a work of sarcasm.

Re:Anti-Cold

[NanoGator]

"Not really. But I have a hypothesis that it has something to do with heat or as I call it, "anti-cold."

I like how people bitch about the lack of 'news for nerds' on this site lately. Then, when something comes along that's truely nerd worthy, everybody becomes a smart ass.

Re:Anti-Cold

[TimeTraveler1884]

Unless, of course, this is a work of sarcasm.

[sarcasm]Nooooooo...[/sarcasm]

Re:Anti-Cold

[Anonymous Coward]

[sarcasm]Nooooooo...[/sarcasm]

Vader?

Re:Anti-Cold

[Anonymous Coward]

I like how people bitch about the lack of 'news for nerds' on this site lately. Then, when something comes along that's truely nerd worthy, everybody becomes a smart ass.

You're saying "why ice melts" is "stuff that matters"?

Re:Anti-Cold

[learn fast]

The real reason of course, which you wouldn't know from reading the pseudo-scientific raving of the parent poster, is that melting is an adaptive response to a changing environment.

You see, most water was burned at an earlier time. So, when it encounters heat it melts out of fear! It melts to more effectively evade what it expects might be a dangerous encounter. This also explains why water melts faster when it is shaken upside-down and verbally threatened.

Some people think that this proves that water is less-than-rational, however it's clear to me that it is an adaptive response. The kind of therapy that would get it out of that kind of feedback loop is much to expensive for most water to afford, anyway. Most people don't realize that there are whole water galaxies, where water can more easily acheive economic unanimity.

This simple theory explains so much evidence. Why do we see so little water inside of volcanoes? Inside of airplane engines? Or inside of stoves? It's because water fears heat! Based on an earlier, traumatic reaction that must have occurred sometime in its past.

I'll be here waiting for my Nobel Prize. Is the king of Sweden's daughter hot? Prolly.

Re:Anti-Cold

[kfg]

Which goes to show that nerdiness causes smartassiness. D'oh!

KFG

Re:Anti-Cold

[Anonymous Coward]

With 1,000,000 users of this site what makes you think the people bitching that the news is not for nerds are the same people that are being a smart-ass?

Re:Anti-Cold

[uttaddmb]

Oh, if only Vader was being sarcastic.

Re:Anti-Cold

[Anonymous Coward]

It's funny. Laugh.

Re:Anti-Cold

[ToastyKen]

If you don't think that matters, then you certainly don't qualify as a "nerd". :P Basic science is all about finding out how the world works, without necessarily having any obvious utility for that knowledge. A couple of days ago was the 100th anniversary of Einstein's publication of the theory of special relativity. Did that "matter" at the time?

Re:Anti-Cold

[Golden_Eternity]

I think the point is that most of us have grasped the concept of ice melting since we were old enough to sit at the big table. More so after intro to physical science in high school when we learned the magic of Celcius.

Re:Anti-Cold

[elgatozorbas]

I think the point is that most of us have grasped the concept of ice melting since we were old enough to sit at the big table. More so after intro to physical science in high school when we learned the magic of Celcius.

There is a difference between knowing ice melts and knowing why or how. The Greek also knew that every day Apollo would ride his sun-chariot. No need to investigate how he did this exactly.

As the parent said: nerds want to know how stuff works.

Re:Anti-Cold

[Anonymous Coward]

We get a blurb that begins with "Ever wonder how ice melts" and you are surprised that people make fun of it?

Re:Anti-Cold

[Anonymous Coward]

Duh! It's "News for Nerds", not "News for Well-adjusted Individuals with Manners"!

Re:Anti-Cold

[MidnightBrewer]

It's just our way of expressing our joy in the nerd-worthiness.

Re:Anti-Cold

[Anonymous Coward]

Is the king of Sweden's daughter hot? Prolly.

Yes. Zee for yourzelf. We are proud of her.

http://www.princess-madeleine.com/

Re:Anti-Cold

[Anonymous Coward]

You see, most water was burned at an earlier time. So, when it encounters heat it melts out of fear

Was that when it was a clam? Or perhaps in the bladder of Piltdown Man?

What would happen if I opened and closed my fingers at it?

Re:Anti-Cold

[gilroy]

Blockquoth the poster:

Then, when something comes along that's truely nerd worthy, everybody becomes a smart ass.

Oh, I'm pretty sure they're already smartasses; they just get the opportunity to show it off... :)

Re:Anti-Cold

[Anonymous Coward]

>A couple of days ago was the 100th anniversary of Einstein's publication of the theory of special relativity. Did that "matter" at the time?

Not really, but it's all relative anyway.

Re:Anti-Cold

[chadpnet]

Given the sarcastic nature of your reply, I would have to agree that your hypotheses is accurate as you, and now me, continue the recursion.

Re:Anti-Cold

[Anonymous Coward]

I know you are just being a smartass, but freezing and melting really aren't as simply as: below 0 C=frozen and above 0 C=melted.

Get a plate or lid or some flat object. Smear a thin layer of oil on it and put small drops of water on this. Stick it in the freezer and check on it periodically. You may be surprised to find that after 10 minutes of temperatures well below 0 C that several of the drops still remain liquid. The drops have certainly cooled to below freezing, yet they still remain liquid. For best results use distilled water and boil it beforehand to remove the disolved air.

The reason this happens is that ice needs a nucleation site in order to get the crystal started. At the temperatures in your freezer there is still enough energy in the water molecules that they are unlikely to spontaneously group themselves - they need an impurity to fall in that they will crystalize around. This is while distilled water will prolong the time the drops remain liquid.

So it really isn't as simple as increasing or decreasing the heat.

BTW the above experiment comes from Craig Bohren's ``Clouds in a Glass of Beer''

Re:Anti-Cold

[Anonymous Coward]

http://en.wikipedia.org/wiki/Image:Victoria%2C_Cro wn_Princess_of_Sweden.jpg

http://en.wikipedia.org/wiki/Image:PrMadwebb2.jpg

The two princesses of Sweden - I'd have to say you're right. Of course, you're obviously a geek, so... no chance ;-)

Re:Anti-Cold

[WindBourne]

but only when I am properly funded by government grants.

Man, we have things wrong. Screw the grants.

1. Create a company. Call it hulliburton.
2. Hire one of the bush twins and label her as CEO.
3. Get LOTS of government money for nothing.
4. PROFIT!!!!!

Re:Anti-Cold

[Anonymous Coward]

The Crown Princess is okay, but her younger sister isn't really.

Re:Anti-Cold

[Strawser]

Kind of similar to boiling point and it's tragic relationship with Pyrex measuring cups and microwaves. http://aca.ninemsn.com.au/factsheets/575.asp

In short, since the container doesn't have any flaws or any major points of differing temperature, no steam bubbles ever form, so the water never begins to roll. Instead, it just sits there absorbing heat until you finally take it out and drop a spoonfull of instant coffe or something in it, and it explodes and burns your face off.

Re:Anti-Cold

[ImaLamer]

I like how people bitch about the lack of 'news for nerds' on this site lately. Then, when something comes along that's truely nerd worthy, everybody becomes a smart ass.

It's like when you go into a strip club: suddenly you are an expert in taste and "this" or "that" woman isn't good enough for you.

Doubt me? Look at the women outside of the club you wouldn't mind sleeping with - then go into the club and watch how you hold those dollars so tightly.

Re:Anti-Cold

[Anonymous Coward]

I think you're forgetting that a lot of the "nerds" around here are engineers and not scientists. I think how the two groups differ can be seen in each's response to this finding.

Re:Anti-Cold

[antispam_ben]

I think you're forgetting that a lot of the "nerds" around here are engineers and not scientists. I think how the two groups differ can be seen in each's response to this finding.

I'm an engineer by profession but am very interested (and perhaps even fairly knowledgable) in science. I'd like to think this is typical of engineers, and it certainly is of some (much more so than nontechnical professions).

I would have liked to have had more pure-science-oriented classes in college (a smallish engineering school with a 'physics and chemistry' department which had no degree path, only offering classes required for other degrees), but with the "publish-or-perish" paradigm of the scientific profession, it's just as well I didn't become a "professional scientist."

I have this CD of all "The Amateur Scientist" columns ever published in Scientific American, and I highly endorse it (I have no connection other than happy buyer) for other True And Pure Science Nerds:
http://www.brightscience.com/

Re:Anti-Cold

[zo219]

". . . everybody becomes a smart ass."

But that's the best part! Wait. Okay, you're saying there's some other reason to read /.

I have to go think.


Draft sig: Geeks: lousy lovers, and the funniest men in print.

What else don't we know?

[bensafrickingenius]

I guess I thought we woulda had this one nailed down by now! What will scence reveal that we don't know next?

Re:What else don't we know?

[Mazem]

Hey, thats a serious point - the world is not flat, the earth is not the center of the solar system, objects in motion do not naturally tend to stop without outside influence, the world was not made in 7 days, time is not independant of your frame of reference, at a microscopic level the world is not deterministic, etc... Often the most fundamental discoveries in science show that we don't know what we thought we knew.

Re:What else don't we know?

[Mozk]

at a microscopic level the world is not deterministic
Can you provide an article? I was always interested in determinism.

Re:What else don't we know?

[Mazem]

If you observe a particle, its wavefunction collapses in an irreversable process. Before the measurement is made, there is no way to know for sure where the particle will collapse to when you observe it (You just have a wavefunction of probability amplitudes), and so it the position of the particle is not deterministic. Thus Einstein's comment "God does not play dice". The weird thing is that if you could never actually observe anything, the universe _would_ be deterministic. The wavefunctions that describe the probability amplitudes would just spread out and interact in a perfectly predictable way via wave mechanics.

Re:What else don't we know?

[coopex]

This is just a minor correction - in the back of Griffiths QM it mentions that it is still an unsolved problem whether a particle has an indeterminate or determinate position before you observe it and collapse its wavefunction.

I don't understand what you mean when you say if you don't observe it the universe is deterministic - it's governed by wavefunctions of probabilities, so you'd know that A has X% chance of happening, B has Y%, etc..., but it wouldn't make it deterministic in the least

I know!!!!!!

[Anonymous Coward]

I'll teach those who don't know. ice melts so it matches the room tempr.

It's about time...

[SpartanVII]

I can finally sleep at night!

Ever wonder..?

[tetrahedrassface]

Ever wonder why Earths orbit is fairly round.. while most other planets are elliptical?

I think matter is ON crack...\

Re:Ever wonder..?

[Anonymous Coward]

Because elliptical orbits give rise to large temperature changes throughout a full revolution, and so life is much more likely to evolve on a planet with a more stable, circular orbit?

Or God did it, whatever.

Re:Ever wonder..?

[delirium of disorder]

Other planets are more stable (climate wise) then earth, but their normal temperatures are probably too extreme to sustain life.

Venus' orbital eccentricity: 0.00677323
Neptune's 0.00858587
Earth's: 0.01671022

Venus' surface temperature ranges from about 820 degrees to nearly 900 degrees F

Earth's surface temperature ranges from about -80 degrees to around 130 degrees F

Neptune's mean cloud temperature ranges from -315 to -307 degrees F (Temperature varies vastly by cloud elevation, but probably little across the same cloud level)

Re:Ever wonder..?

[Anonymous Coward]

Well there are other reasons why there is no life on Venus, the atmosphere being a big one contributing to that temperature.

If Venus had less greenhouse gasses it would still be uninhabitable, but it would be a drastically lower temperature.

But of course, the temperature is the reason for so much gas and the gas is the reason for so high a temperature. Though the proximaty to the Sun started Venus with too high a temperature, while we were lucky enough to start in the "sweet spot".

Always has seemed a pity that Venus turned out that way, it's like Earth's trippy, drugged-out older sister. If the temperatures weren't so nasty and the atmosphere lighter it could have been a create first place to colonize.

Re:Ever wonder..?

[Anonymous Coward]

Earth's seasonal are primarily the results of the Earth's axial tilt, not the elliptical orbit. (In fact, the Earth is closer to the Sun during the Northern hemisphere's winter than during its summer). With the exception of Pluto, the rest of the planets in the solar system have similar elliptical orbits.

Re:Ever wonder..?

[Anonymous Coward]

But of course, the temperature is the reason for so much gas and the gas is the reason for so high a temperature. Though the proximaty to the Sun started Venus with too high a temperature, while we were lucky enough to start in the "sweet spot".

Always has seemed a pity that Venus turned out that way, it's like Earth's trippy, drugged-out older sister. If the temperatures weren't so nasty and the atmosphere lighter it could have been a create first place to colonize.

It's possible that Venus was the first place "colonized". Ok, that's trippy, drugged-out thinking, but perhaps Venus used to be like Earth, and the inhabitants messed up their environment royally. With the current atmospheric pressure and acid rain, any evidence of civilization there would be wiped out by now.

I'm not saying it happened, but it would explain lots of unexplicable stuff quite neatly: Pyramids...UFOs...Republicans...

Re:Ever wonder..?

[baadger]

...Women

"Men are from Mars, Women are from Venus"

gaining a firm grasp on the physical world

[xafan]

Because we all need firm grasps on liquids!

Re:gaining a firm grasp on the physical world

[Deltaspectre]

Yes! Then I have no need to use a cup for holding my liquids!

Zap!

[AussieVamp2]

Matta-Cracka (tm) disintegrator ray discovered in pub? :)

Not suprising

[cyberfunk2]

This is somewhat akin to boiling really, at least from my perspective.. small nucleation points, that spread throughout the liquid or crystal, effecting an overall phase change when the energy distribution reaches a point such that the majority of atoms prefer the gaseous or liquid state (depending on the phase change).

Re:Not suprising

[Saturn49]

Along the same lines, I would think that a very pure, well-formed crystalline solid would be able to be super-heated, then jarred and the whole thing would melt instantly.

Googling for superheated solid returned a bunch of research papers, but that was about it.

Re:Not suprising

[cyberfunk2]

Unfortunately, I believe there are natural nucleation spots built into a crystal.. that is, where the crystalline material ends and meets the atmosphere... In an idealized crystal, say, a NaCl crystal structure that has a 6:1 coordination for each atom of Na to Cl (or vice versa), the corners of the perfect crystal would only coordinate to 3 of the opposite atom, causing some sort of a difference in the suceptibility of the atoms at the very surface or corners of the crystal (I've actually always been somewhat curious as to how crystals "terminate"). In any case, this would likely be where the melting would start. As a chem major, i've seen plenty of super cooled liquids, but never seen a superheated solid (although it's completely possibly i'm just unexposed to such a phenomenon), and I would guess because it's because of the reason i just cited (although, I admit, it's pure speculation). Also, perfect "single" crystals (as used in good Xray diffraction experiments) are somewhat difficult to form from even relatively simple compounds (it's even more trying with complex organic compounds). The only superheating i know of is of a liquid above it's boil point (again, like with liquid to solid , needs nucleation points)

Re:Not suprising

[cyberfunk2]

Perhipherial support of my argument that I found after looking around:

http://phycomp.technion.ac.il/~phsorkin/Seminar/co at.html

Re:Not suprising

[eaolson]

Melting does generally begin at a surface or crystal defect, which is doesn't really require nucleation, like crystallization does. Many metals (which are just the materials I'm familiar with) actually have a nanometers-thin, liquid-like layer at their surface below their melting temperature. Therefore, the liquid has already nucleated before the material gets to its melting temperature.

It is possible to superheat crystalline solids but it requires ultrafast heating (multiple thousands of degrees per second and up), and is not possible in all materials systems.

You are also right in that "dangling bonds" at the surface of a crystal are odd. Surface atoms will often rearrange into particular structures to reduce the surface energy of just the bare surface. It's called reconstruction, and has been widely studied in silicon.

Wait...

[Anonymous Coward]

Wait wait wait, let me get this straight. We put a man on the moon, developed flying machines composed of several hundred tons of steel, and we just now BARELY explain why Ice Cubes melt in our drink? You know, sometimes humanity really is....scary. What'll be truly frightning is if scientists come out with an explanation as to why Ice Cube still gets movie roles.

Re:Wait...

[PxM]

What people fail to understand is how strangely complicated the world is. Putting a man on the moon is a matter of figuring out the proper nonlinear dynamic control equations which is pretty much classical physics and (really hard) math. Something like the thermodynamic properties of matter at a molecular level requires a lot more research due to how freaky the universe gets at that small of a scale. Similarly, figuring out how the human body works (modern medical science is akin to fixing a car with a sledgehammer, chainsaw, and sulfuric acid) is also hard due to the complexity of physics on the molecular scale. That's why we can put a man on the moon, but can't cure cancer or even the common cold.

Re:Wait...

[simcop2387]

lets just hope he doesn't get a starring role next to kevin costner, the movie goers would go braind dead trying to figure out how the movie got funding.

Re:Wait...

[coopaq]

You know, sometimes humanity really is....scary.

Ahhh good old /. readers

I guess I'm glad the story wasn't "Every wonder how babies are made?"

Re:Wait...

[damsa]

Dances with Next Next Next Friday. I would watch that.

Re:Wait...

[jpostel]

One of my college professors in materials science, that retired from Bell Labs to teach, used to say, "I'm pretty sure this is how it works, but I'm not positive. If anyone tells you he is positive, he's either lying, or not smart enough to check that the underlying facts are actually suppositions."

He once told us that he didn't really know how resistors worked, but he did know that if he manufactured them using certain materials in a certain process, he could get resistors that were a certain number of ohms. Today resistors are manfactured all over the world pretty much the same way, but the methods were derived from trial and error, and not some deeper understanding and equations for making the best resistor.

Re:Wait...

[XSforMe]

we just now BARELY explain why Ice Cubes melt in our drink?
The introduction to this article (as well as its summary, since its a plagerized C&P job) are prime examples of sensationalistic journalism. A more adequate description would be how ice melts, since it deals with the molecular mechanics of water molecules when the melting starts, rather than the fact of why heat transfer triggers the melting process.

Re:Wait...

[MutantHamster]

Even more amazingly, we still don't know the difference between "how" and "why"!

Re:Wait...

[renehollan]

Ice cubes? In my drink? In my single malt scotch?

I don't f-ing think so.

I remember on once ordering a Macallan at the bar in the Mickleover Hotel in Derbyshire, and the barmaid asking me if I wanted it "on the rocks". She quickly recovered from my look of absolute horror, and said, "So sorry, from your accent, I'd thought you were American. Neat it is, then. Very good."

Ever wonder why ice melts?

[Omkar]

a. Summary is plagiarized from the article, unless I've missed some nested quotes.
b. These guys took this problem because "the earliest phase of melting has never been seen" but they didn't do that either! All they did was make "see-through crystals that are like small beads and are visible in an optical microscope." Doesn't sound like a hell of a lot of progress to me; anyone care to elaborate?
c. Their main result seems to be that the melting process starts at crystal defects and spreads to create liquidy regions within the crystal. Again, can anyone explain why the melting might not start at defects - the weak points?
I'm sure there's something neater here than I'm seeing; it would be nice if the article had more info.

Re:Ever wonder why ice melts?

[albn]

Yes, I was wondering what this discovery will actually pave the way for. I am sure somebody will figure something out. Personally, I am still waiting for the solution for Superstring theory.

Re:Ever wonder why ice melts?

[stwrtpj]

a. Summary is plagiarized from the article, unless I've missed some nested quotes.

Just curious as to why you state this implying that this is a problem. I prefer it this way myself. I much rather would see the opening summary paragraph verbatim from the article rather than someone's interpretation of it. Too many times in the past, something gets lost in the translation, or the article is made to sound more sensational than it is.

Re:Ever wonder why ice melts?

[Omkar]

I agree with you, but I wish the guy gave credit where credit is due.

The awesome power of Pykrete!

[Grendel Drago]

Speaking of ice, have folks here ever heard of Pykrete? And would this explain why Pykrete melts so slowly?

Supposedly tissue paper works as well as sawdust. So you can tell all your friends you know how to beat someone to death with a wet paper towel.

--grendel drago

Re:The awesome power of Pykrete!

[repvik]

Pykrete melts so damn slowly due to the low thermal transfer rate of th wood pulp. Didn't you ever have physics? Don't you read the wikipedia links you paste? ;-)

Re:The awesome power of Pykrete!

[suwain_2]

Why 14%, I want to know. Is it better than 15% or 13%, or did he just try 14% and find that it worked well? I think I've found an experiment for a slow day.

Re:The awesome power of Pykrete!

[ErikZ]

I've heard, back when people had ice delivered to them, they would store it by covering it in sawdust.

Re:The awesome power of Pykrete!

[Dolly_Llama]

From the article: "You could use it to make cold compresses that mold to your body and last quite a while."

Isn't the whole idea of cold compresses to cool? Might as well have a very cold piece of foam.

Re:The awesome power of Pykrete!

[rhakka]

My old home in maine used to have a shingle mill behind it, so when we moved in, there was several feet of sawdust covering the ground for part of our large backyard.

One July a year or two after we moved in, I was digging around amusing myself, and to my surprise, there was a chunk of ice about six inches down. Apparently a little "stream" (more like a seasonal rivulet) had frozen the previous winter and hadn't gotten around to melting yet.

Since we had been solidly above freezing for more than 3 months, I was pretty impressed.

Re:The awesome power of Pykrete!

[Anonymous Coward]

Yeah, my grandfather and his brothers and dad had a wholesale ice business in New York, back in the day. They'd cut blocks out of the Hudson in the winter. Then store them under mounds of sawdust, in barns and sheds on various farms up the river. In the summer, they'd sell it in bulk to Nickerbocker Ice.

Until the year when Nick Ice tried to drop the wholesale price in half. So they rented wagons, and sold the ice to the public at the price they used to get from Nick. After about 2 months of pretty hot spring and summer, Nickerbocker came crying back and even offered a raise on the initial wholesale price. They didn't sell nearly as much during their stint as retailers as they would have to Nick, but they did do enough of a business to get Nickerbocker to cave. What Nick had underestimated was how LONG the ice could keep, buried under all that sawdust.

wow

[Anonymous Coward]

all of these comments are only moderatly funny...i would have expected more

Maybe...

[Michael_Munks]

now we can finally fix Genine Garofalo, Hilary Clinton and Rosie Odonnell.. Yeah?

Re:Maybe...

[Adrilla]

First we gotta fix some of that spelling you've got there. Janeane Garofalo, Hillary Clinton, and Rosie O'Donnell

Great...

[Anonymous Coward]

Now how long till they can whip-up a batch of Ice-Nine and freeze the whole planet?

Re:Great...

[haakondahl]

You mindless troll, this research was only into how ice melts, not how it might undergo some sort of "unmelting" process. Please try to keep your comments on-topic--if you want to posit outlandish crankful theories, go somewhere else. Yes! Yes!

Re:Great...

[ChodeMonkey]

Curiously, Ice Nine is real, but it does not have the odd properties predicted in the Cats Cradle. In fact there are some thirteen forms of crystalline ice that are known to exist.

Pretty humbling, if you ask me

[Sensible Clod]

As much as we know about the universe, life, and everything, there's 10^x more that we don't know, even about things as simple as this.

</serious>

In other news, scientists have come up with an astonishing new explanation of how paint dries! Film at 11.

Re:Pretty humbling, if you ask me

[Anonymous Coward]

Um...basically, no. 10^x is big. So big, in fact that if we made, say, 1 billion discoveries (conservative IMHO), it would be 10^1000000000. Now that doesn't jive with the fact that there are well under 10^100 atoms in the entire visible universe.

Hang on

[Entanglebit]

Wait a minute... wait a minute. We never knew how ice melts? Is this guy serious?

Killer Instinct is Robert Roy Britt?

[Osty]

From the article submission:

Until now, scientists could not explain why ice cubes in your drink melt. They've known the basics, but the details remained elusive. A breakthrough new study, announced yesterday, supports a leading theory that melting starts when the fundamental structure of matter begins to crack. Melting is considered a basic phenomenon in physics. An understanding of how it works is crucial to gaining a firm grasp on the physical world.

And from the actual article itself:

Until now, scientists could not explain why ice cubes in your drink melt. They've known the basics, but the details remained elusive.

A breakthrough new study, announced today, supports a leading theory that melting starts when the fundamental structure of matter begins to crack.

Melting is considered a basic phenomenon in physics. An understanding of how it works is crucial to gaining a firm grasp on the physical world.

Those look pretty similar to me! Given that the article submission is word-for-word exactly from the article itself, it's fair to assume that the submitter, Killer Instinct, is the same person as the author of the article, Robert Roy Britt. How else could the same text be attributed to two supposedly different people?

If you're going to submit an article, summarize it in your own words. If you're just going to paste in the first few sentences of the article, attribute them to the proper author by using a phrase such as, "Quoted from the article: 'insert quote here'." Removing line breaks is not enough to satisfy the "summarize in your own words" criteria.

Here's an example of what the submission should've looked like if Slashdot cared at all about given proper attribution for written text:

Killer Instinct writes "Ever wonder how ice melts? From the article: 'Until now, scientists could not explain why ice cubes in your drink melt. They've known the basics, but the details remained elusive. A breakthrough new study, announced yesterday, supports a leading theory that melting starts when the fundamental structure of matter begins to crack. Melting is considered a basic phenomenon in physics. An understanding of how it works is crucial to gaining a firm grasp on the physical world.'"

Re:Killer Instinct is Robert Roy Britt?

[vga_init]

Mod parent up, please

Re:Killer Instinct is Robert Roy Britt?

[FFFish]

Gosh, I'd thought it was the editor's responsibility to check legitimacy and attribution were correct.

Re:Killer Instinct is Robert Roy Britt?

[phalse phace]

Killer Instinct probably thought that since no one really bothers to RTFA anyways, that s/he'd be safe. Guess not.

Re:Killer Instinct is Robert Roy Britt?

[Anonymous Coward]

Of all the stupid and annoying things slashdot editors do, this is pretty petty and harmless. I'd be happy if they just read the damn site every day and acted like they cared for the users rather than being annoyed by us.

Correctly summarize the article? Who gives a crap, we're lucky if 50% of the people leaving comments even got past the title. Pick your battles.

Re:Killer Instinct is Robert Roy Britt?

[i]

Who cares ???

Re:Killer Instinct is Robert Roy Britt?

[rich_r]

Those look pretty similar to me! Given that the article submission is word-for-word exactly from the article itself, it's fair to assume that the submitter, Killer Instinct, is the same person as the author of the article, Robert Roy Britt. How else could the same text be attributed to two supposedly different people?

Plagarism?

Or was that a rhetorical question... But honestly, you must be new here- it happens all the time!

Re:Killer Instinct is Robert Roy Britt?

[jpostel]

Slashdot has editors? Although the banner has the word News on it, it's not quite journalism.

Then again, most newspapers just reprint stuff from the AP and other sources. Hmmm.

Maybe Slashdot is a legit journal and news agency. If so, I expect the highest quality and standards of journalistic integrity from the editors and writers. Slashback can now be used for retractions and appologies for all the mistakes and re-posts of old articles and grammar mistakes and...

Hey... where'd my Karma go? ;p

Re:Killer Instinct is Robert Roy Britt?

[bogado]

I have noticed this long ago. A simple cut and paste from the first paragraphs is what many people do to post here. This work like a charm, since most articles resume themselves in the firsts paragraphs so people that stop reading can get the idea of what is it about.

That pratice hides what people think, their individuality, their self. It is no better then a news agregator. What make's slashdot different from a machine is the people, but for better "scores" people sundenly start acting as machines. If only slashdotians could think less in terms of scoring, slashdot is not a game.

Re:Killer Instinct is Robert Roy Britt?

[Osty]

Then again, most newspapers just reprint stuff from the AP and other sources. Hmmm.

When newspapers reprint from AP, Knight Ridder, Reuters, or other wire services, they give attribution. However, there's also a level of trust for wire services, such that if a wire service is referencing another article verbatim, they're expected to quote it. In that respect, Slashdot is similar to a newspaper using wire service articles that reference other articles. Like newspapers, Slashdot gives credit to its direct source (wire services like AP for papers, the submitting user for Slashdot). Unlike newspapers, Slashdot should not assume its contributors have the same level of integrity as a wire service, and thus should check references (or pick a different submission, since I'm sure any story that gets posted also has multiple submissions in the queue, or how would duplicates happen?).

Slashback can now be used for retractions and appologies for all the mistakes and re-posts of old articles and grammar mistakes and...

Or they could update the stories directly, as they've done in the past. Print media can't really do this, so they have to print retractions.

Oh FFS!

[Anonymous Coward]

People keep bitching that this is News for Nerds, but when something really nerdy comes up, suddenly everyone is just too good for it!
Fucking hypocrites.

STNNZXF

Next problem - Wicked Witch of the West

[tinrobot]

She's melting! She's melting!

Captain Obvious to the Resue!

[Maniakes]

Step 1: Ice gets warmer.
Step 2: Warm ice turns into liquid water.

What's not to understand?

Re:Captain Obvious to the Resue!

[Maniakes]

Captain Obvious apparently knows not how to spell "Rescue".

Re:Captain Obvious to the Resue!

[no-karma-no-worries]

Step 1: Ice gets warmer.
Step 2: Warm ice turns into liquid water.

Step 3: Profit!

Re:Captain Obvious to the Resue!

[Anonymous Coward]

Captain Obvious apparently knows not how to spell "Rescue".

Thank you vary much Geniral Grammer!

-Admiral Asshole

Re:Captain Obvious to the Resue!

[nametaken]

Step 1: Ice gets warmer.
Step 2: Warm ice turns into liquid water.


Wait, wait... could you explain that from the beginning?

Seriously, you should have gotten the grant money for this. :)

Re:Captain Obvious to the Resue!

[Anonymous Coward]

No, you've explained what causes the ice to melt. The question is why does it melt when exposed to those conditions?

We know that nuclear fusion powers the sun, but why does the fusion occur?

Actually...

[Sensible Clod]

if the hot water bucket is hot enough, and the 'cold' one is at about room temp, the hot water bucket will lose a significant amount of caloric energy and mass through evaporation, whereas the cooler one will lose far less. Under some circumstances, this actually does lead to the hot water's freezing before the cooler one does, partly because there's less water there to freeze.

Ah, as usual....

[jtbauki]

...smartass slashdotters crack jokes about a new discovery to hide their own insecurities. I, for one, freely admit I have no idea how ice melts.

1+1=2 anyone?

Re:Ah, as usual....

[Anonymous Coward]

1+1=2 anyone?

I'm sure that the average person doesn't know that either.

Accuracy ?

[cyberfunk2]

At least the way the article describes the study.. it doesnt seem like it models the problem well.. but something tells me these arent the greatest writers here... For instance:

"So Yodh's team made some big atoms. Specifically, they made see-through crystals that are like small beads and are visible in an optical microscope."

By "see-through crystals" i'm assuming they mean optically transparent crystals constructed from small beads, not crystals that are like beads that then form a larger crystal structure, although from the wording, it's impossible to tell.

"The spheres swell or collapse significantly with small changes in temperature, and they exhibit other useful properties that allow them to behave like enormous versions of atoms for the purpose of our experiment,"

As far as I know.. atoms dont significantly change size when temperature changes.... they change how fast they move. I dont really see how size-changing beads model water molecules here, unless it's on a macroscale where a molecules are considered to expand as a group with increased temperature... but that sort of would defeat the pupose of the whole study...

On the other hand.... I think that the research is probably solid, espcially if it's being published in Science, a extremely selective journal. I think the article just fails to explain it well, and takes quotes out of context. Sadly, this is all too common in scientific journalism.

Re:Accuracy ?

[Anonymous Coward]

The work is nice enough, but it's absurdly overhyped in the summary. This doesn't tell you dick about how ice melts, because a colloidal crystal is nothing like an accurate model of ice. The hydrogen-bonding network in ice (and water) makes it radically different in its dynamics and phase behaviour from a colloidal crystal.

This work may give you some thoughts on how something like solid argon or xenon melts, because those crystals could be plausibly modelled by a colloidal crystal, but it says very little about ice.

Re:Accuracy ?

[Hsien]

I for one am getting sick and tired of science rejects finding jobs as scientific journalists. I can understand that they need to 'dumb-it-down' for the mainstream, but its 1 thing to simply a concept, and another to abuse and rape it.

Boiling Point, Stupid!

[__aaclcg7560]

I think the opposite problem is more interesting: Why does liquid take forever to get to the boiling point and then rapidly increase in temperature?

I always burn the gravy sauce since I'm distracted when it finally reaches the boiling point. Cooking should be easier than this.

Re:Boiling Point, Stupid!

[k98sven]

I think the opposite problem is more interesting: Why does liquid take forever to get to the boiling point and then rapidly increase in temperature?

Problem solved: Liquids don't increase in temperature once they've reached their boiling point. Not as long as its in an open container so the surrounding pressure is constant.

Once you reach the boiling point, the heat you add doesn't go towards raising the temperature, but towards vaporising the liquid.

Re:Boiling Point, Stupid!

[elbarono]

That question doesn't make sense. When liquid reaches its boiling point, it turns into a gas. It doesn't rapidly increase in temperature. It stays at the boiling point until all of the liquid has turned into gas. After that, the temperature of the gas can start increasing again.

Burning is oxidation (a chemical reaction) and has little to do with boiling (transition from the liquid to gas state of matter)

Re:Boiling Point, Stupid!

[benna]

It doesn't...once a liquid gets to the boiling point, it becomes a gas.

Re:Boiling Point, Stupid!

[Anonymous Coward]

Once it is at boiling temperature it should stay at a constant temperature unless you have managed to seal the pot (prevent evaporation/steam) and your vessel is insulated enough over enough of its surface that the energy entering through the element against the base is greater than that lost by radiation from the pot.

As for burning your sauce - this is because the proteins in your sauce are sticking to the bottom and becoming charred. As they are stuck to the bottom of the pot, the heat transfer is beyond the standard boiling temperature (a little over 100 degrees Celsius due to boiling point elevation) in the rest of the sauce.

Simply put, to prevent burning your gravy sauce, either cook using a bain-marie (ie. cook sauce in a pot that sits in a pot of boiling water), or cook the sauce in a microwave :)

Re:Boiling Point, Stupid!

[__aaclcg7560]

Simply put, to prevent burning your gravy sauce, either cook using a bain-marie [wikipedia.org] (ie. cook sauce in a pot that sits in a pot of boiling water), or cook the sauce in a microwave :)

Bingo! I'll try that next time. :)

Re:Boiling Point, Stupid!

[Kaboom13]

This is actually easily explained (although I suspect you were joking). Any liquid, including gravy has 3 important heat related constants. The "specific heat", which is how much heat is required to raise 1 kilogram of a substance 1 degree kelvin. The "heat of fusion", which is how much heat must be removed per kilogram to freeze the substance, and the "Heat of vaporization" which is how much heat must be added to vaporize (aka boil) the substance. The Specific heat of water is (from memory so I may be off) 4180 J/(kgK) and the heat of vaporization is 2260 kiloJ/kg. So to to raise 1 kg of water from 0 to 100 degrees celsius is 418 kJ, to boil that water away requires 2260 kj. So as the water in your gravy finishes boiling away, the process that has been consuming large amounts of heat stops, and by now you have a smaller mass to heat and a very hot stove. The new solution requires less heat to raise in temperature and will heat up much more quickly.

Re:Boiling Point, Stupid!

[__aaclcg7560]

Initially, I was joking. But when the solution on how avoid burning the gravy became apparent, I got excited. Cooking gravy has always been my weak point when I was working in the resturant business for a few years.

Re:Boiling Point, Stupid!

[Anonymous Coward]

Check out book by Strogatz: Sync.

Re:Boiling Point, Stupid!

[jtdubs]

The key is that water has a high specific energy, so it can absorb a lot of energy without actually increasing in temperature. The other types of molecules in your gravy solution can happily be heated to over 212 degrees without boiling; only the water boils. As more and more water cooks out of the gravy, there becomes less water to absorb the energy through evaporation so the energy begins heating the remaining non-water liquid to a higher temperature than water's boiing point.

This is the entire methodology of fudge making. Create a sugar-water solution. Apply heat. It gets to 212 slowly. Water begins to evaporate. Sugar continues to heat, driving the temperature of the solution above 212 degrees. The less water there is the less resistance there is to moving above 212. At the appropriate temperature (235 degrees; soft ball stage) you remove the solution from the heat and let it cool. You now have fudge. Ideally you would also add corn syrup, chocolate, cream instead of water, butter and vanilla extract (at the end) to improve the flavor. And hopefully you would stir vigorously once it drops below 150 or so so that the sugar crystals that are created are as small as possible and your fudge has a smooth texture. :-)

Caramel is made in the same way. Heat the sugar-water solution to just before the burning point for sugar (around 350), add cream, boil for 3 minutes then cool. Youv'e got caramel!

Mmmmm.... food....

Justin Dubs

Re:Boiling Point, Stupid!

[value_added]

I think the opposite problem is more interesting: Why does liquid take forever to get to the boiling point and then rapidly increase in temperature?

That's easy. Everybody knows that water will come to a boil faster when you're not watching it.

Schroedinger's cat meets the melting is an adaptive response to a changing environment theory.

Re:Boiling Point, Stupid!

[XchristX]

Latent heat, that's why. Oh, and yes, we don't understand how liquids boil either. At least, we can't explain these basic phase transitions usign models of spontaneous symmetry breaking like Landau did for more exotic phase transitions

Re:Boiling Point, Stupid!

[eaolson]

The key is that water has a high specific energy, so it can absorb a lot of energy without actually increasing in temperature. The other types of molecules in your gravy solution can happily be heated to over 212 degrees without boiling; only the water boils.

You are right in the broad overview, but wrong on the details. The boiling temperature of a mixture is not necessarily due to the boiling temperatures of its two components. The boiling temperature of a solution is not a linear combination of the boiling temperatures of its constituents. It's often close, which is why we have Raoult's law (although it technically deals with vapor pressure, not boiling temperature).

Ethanol and water, for example form an azeotrope, a constant boiling solution, at something like 96% ethanol. It's why you can't distill alcohol to 100% purity. At the boiling temperature of the azeotrope, ethanol and water molecules are evaporating at the same rate, even though the solution is not at the boiling temperature of either.

Re:Boiling Point, Stupid!

[jtdubs]

Thanks for the inforrmation/corrections. I'm more of a cook than a scientist at this point, it seems. :-)

Justin Dubs

Re:Boiling Point, Stupid!

[eaolson]

Hey, I love the fudge analogy. I've just always thought it was more applicable to crystallization than boiling. Then again, I'm a materials scientist and that's what we do. :-)

Not Insightful or Interesting

[TimeTraveler1884]

Stop modding me Insightful. I was fucking joking!

But if people really didn't know that the Celsius scale was defined with 0 as the freezing point of water and 100 as the boiling point; well glad I could be useful. There is no mysterious alien mathematical connection, us humans defined the "connection".

Re:Not Insightful or Interesting

[piglicker]

Jesus... It's a friday night and I've been drinking and I saw the joke! (yes, good joke, btw.)

Funny that you had to tell them :)

Re:Not Insightful or Interesting

[Bartislartfast Simps]

There is no mysterious alien mathematical connection, us humans defined the "connection".

You're just trying to hide the truth from us, aren't you? But you can't stop me, I will not rest until I discover what it is you are hiding from us. The people have a right to know.

Re:Not Insightful or Interesting

[checkyoulater]

But if people really didn't know that the Celsius scale was defined with 0 as the freezing point of water and 100 as the boiling point; well glad I could be useful.

Actually, the original value for freezing in the Centigrade scale was 100 and boiling was zero. It wasn't changed until the mid 1700's.

Re:Not Insightful or Interesting

[Kidbro]

Actually, the original value for freezing in the Centigrade scale was 100 and boiling was zero. It wasn't changed until the mid 1700's.

While what you're saying is true, I think that the way you put it may give people reason to exaggerate the life span of the original scale. The original system was proposed in 1742, and modified to its current version in 1747. Both are years I'd say qualify for the being part of "the mid 1700's".

Reference.

Re:Not Insightful or Interesting

[sl3xd]

Man, you gotta be hating that post...

Then you get modded as 'informative' for informing the clueless that you were joking.

Next topic of research: how paint dries

[Anonymous Coward]

Sounds like another slow day at the lab...

Bad reporting?

[Nigel Stepp]

This article is too bad; there's probably an interesting result here, but it appears to be shrouded in vagueness and analogy.

It's true that the *exact* mechanism for melting has not been "seen", but the concepts really are well known. Our models are good enough that computer simulations can be very accurate. I have seen several which show features such as surface melting, for instance.

Also, it is absolutely expected that melting begin at defects, but this does not mean that "melting begins below the melting point" as the article suggests. These areas are locally amorphous and there is no reason that they should begin melting at the crystal's melting point. Really, it's all in the free energy equations.

I'm guessing that the real result has been butchered by the article.

What Boredom will do to you...

[Rylz]

Wow... I just realized that I read a whole article about ice melting... And I was interested. I guess that's what you're reduced to when you have nothing to do but read Slashdot at midnight on a Friday...

C'mon now...

[jnelson4765]

This was already known in metallurgy - metals that fail near their melting point have distinctive micro-structures where certain regions inside the metal have melted.

OTOH, It's been a while since I've cracked a metallurgy text...

Re:C'mon now...

[Anonymous Coward]

Well, all failure of crystaline solids is linked to the propagation of defects through the material. In essance, a tiny defect near the surface can move through the object with a somewhat "ratchet" like effect (I find it hard to explain without pictures) creating lines, and therefore planes, on which the solid can slip past itself.

While this only applies to deformation by pressure, I can easily see how a similar thing can happen in total deformation (like melting) if the defects where pushed through the material by heat energy instead of mechanical energy.

Also, almost all crystals have defects, the perfect crystal is generally considered a theroetical construct that exists at absolute zero (though I believe very close to perfect crystals can be made, the energy in the environment causes various defects automatically)

I am sure that Frosty the Snowman...

[Brad1138]

Is thrilled to know exactly how he will die come spring.

Re:I am sure that Frosty the Snowman...

[WolfWithoutAClause]

Don't bet on it, they may meet Calvin!

http://www.angelfire.com/wa/zzaran/calvin.html

Crazy!

[Jah-Wren Ryel]

An understanding of how it works is crucial to gaining a firm grasp on the physical world.

I did not RTFA, and now I feel like I am tripping on acid - swallowing colors of the sound I hear, I am just a crazy guy.

Slashdot, it's better than drugs!
It will make you innn-sane!!

So How Does Water Freeze?

[guygee]

It turns out that, at the molecular level, nodody knows the answer to this question, either, especially in the presence of impurities. In fact, in general, the subject of "Phase Change" is something of a black art, full of "empirical models", a great dissapointment for a mind that lusts for explanations in terms of hard mathematics. Unfortunately, as a graduate EE taking this course in Chemical Engineering, my grade reflected my disappointment. (Aside: my grad work was done in connection with the Army Corp of Engineers Cold Regions Research and Engineering Lab, thus my unnatural interest in the topic. As the cold war with the USSR gave way to the hot wars in the Mideast, funding for research in the associated topics has dropped off).

Re:So How Does Water Freeze?

[Nigel Stepp]

I don't know, I think it depends on what you mean by hard mathematics. We have the math to explain it, but the equations end up being a lot of stuff written in dirac notation which is an astronomical pain in the ass to actually solve.

At least... this is how it seems to me from my experience studying bonding and crystaline structures (which is a humble: more than most, not as much as many).

Re:So How Does Water Freeze?

[guygee]

The course I took mostly focused on phase change in metal alloys. After some hand waving about the diffusion equation, I seem to recall that most of the rest of the course was based on empirically-derived models attempting to explain crytal formation, size, and chemical makeup of inter-crystalline material, based on rates of change in temperature and pressure, with the goal of predicting the macro-properties of the alloy after creation via some given process. It really seems that scientists do not have a complete picture of the topic, hence the long-held mysteries of the legendary "Damascus Steel".

Hmm.

[millennial]

The caption to this image:
... The circles represent the position of each spherical particle, and the central color of each circle represents the degree of positional fluctuation of each colloidal particle...
Um, uncertainty principle, anyone? How can you measure velocity and position of a microscopic particle?
Of course I'm kidding. I know that we're talking about above-atomic-size particles here... and that measuring positional fluctuation is not measuring velocity, because velocity includes a direction.

Finally...

[Treskin]

the aliens will make contact. It would have been emberassing to make contact with planet that couldn't quite pin down the subtleties of how ice melts.

Re:Finally...

[damsa]

It wouldn't matter as Aliens although mastering the art of space travel and anal probing, cannot master the simple feat of suriving the liquid form of dihydrogen monoxide.

"New [Female] Robot Looks Strikingly Human"...

[Anonymous Coward]

Forget the melting ice!

That's a Japanese scientist in the sidebar with a female robot! So I must ask whether the robot, which does look strikingly human, also has a fully functioning artificial vagina.

More interesting...

[Queer Boy]

Would be if this will lead to learning about how to "melt" other solids. IANAS, so I am just guessing this is the tip of the iceberg [chuckle].

Does carbon ever exist in a liquid state? Liquid diamonds?

Re:More interesting...

[Nigel Stepp]

Indeed, at the right temperature and pressure, carbon will be a liquid. The only problem is that the melting point of carbon is rediculously high.

Re:More interesting...

[The_Chicken_205]

also, that the carbon will most likely react with any oxygen (carbon => wood/coal) in the atmosphere well before this temperature is reached...

Tomorro on /.

[NIK282000]

How paint dries!

125 Questions

[Anonymous Coward]

Was this one of Science's 125 questions?

Ice Spikes

[clockmaker]

Oh, and don't forget, you can use distilled water to make 2" long ice spikes on your cubes!

Materials Science

[Anonymous Coward]

I'm waiting for the perfect anal lubricant.. something that is viscious, not sticky, and doesn't break down during anal intercourse.

Civ

[Anonymous Coward]

Anyone else feel like this is a research tree we just didnt need to get nuclear weapons, sorta like the "Secret of the Wheel"?

Ice-9

[Col. Klink (retired)]

If only they knew a way to melt Ice-9...

How, not why

[thomasdn]

Until now, scientists could not explain why ice cubes in your drink melt.

Scientists does not explain why things happen. Only how.

Re:How, not why

[Anonymous Coward]

Q. Why do giraffes have long necks?
A. A mutation of their ancestors' placed them in less competition for food with shorter herbivores.

Q. Why is the sky blue?
A. A nitrogenous atmosphere favors the diffusion of that portion of the visible spectrum.

Scientists ask and answer the question "Why?" all the time. They interpet the question as "What cause and effect relationships can be established from the physical mechanisms of the system?" What they don't answer is the layperson's definition "What made God think this was a good idea?"

Re:How, not why

[Anonymous Coward]

Indeed; ice cubes melt because it is all part of God's plan for ice cubes. Let us pray for a cool summer and perhaps fewer ice cubes will melt away. Or we could all just drink our Scotch neat.

Re:How, not why

[Anonymous Coward]

this is where we need to go back to the old use of 'why' (as in for what purpose) and 'wherefore' (as in for what reason - answer 'therefore').

scientists ask 'why?' in the 'wherefore?' sense all the time.

modern English has seen fit to do away with wherefore, or rather it acquired the other usage of why and thus became redundant. The only place it's heard is in 'Wherefore art thou Romeo?' and an amazing number of people don't know what that means (although I'm sure all /. readers do). By Shakey's time, he could use it, as here, to have both meanings simultaneously as Juliet is really asking 'for what purpose did the fates choose to call you Romeo?', but when you ask that it becomes both requesting a reason from the past (the reason for the name being the purpose the fates had in mind) and a purpose.

Re:How, not why

[PlacidPundit]

Actually, Science doesn't explain "how" either. Science doesn't explain anything. It only catalogs the ways in which the universe seems to be consistent. Why the universe is consistent, or how the various consistencies relate to each other is not something that can be proven or searched out by observation.

super cooled liquids

[maxwells_deamon]

super cooled liquids and vapors are easy to make.

I have a small fridge here (absocold) it is kind of like the small fridges students use in dorm rooms.

If I put a bottle of water in the freezer compartment
most of the time it will not freeze.

what is fun is to hand it to someone and ask them to shake it or even let me them drink the water.

I will suddenly turn to slush. It is very strange to have water freeze in you mouth.

Abstract

[cyberfunk2]

Abstract from the actual Science article:: Much more informative than this silly article. Premelting is the localized loss of crystalline order at surfaces and defects for temperatures below the bulk melting transition. It can be thought of as the nucleation of the melting process. Premelting has been observed at the surfaces of crystals, but not within. We report observations of premelting at grain boundaries and dislocations within bulk colloidal crystals using real time video microscopy. The crystals are equilibrium close-packed three-dimensional colloidal structures made from thermally responsive microgel spheres. Particle tracking reveals increased disorder in crystalline regions bordering defects, the amount of which depends on the type of defect, distance from the defect, and particle volume fraction. Our observations suggest interfacial free energy is the crucial parameter for premelting, in colloidal and atomic scale crystals.

Superficial Study

[Anonymous Coward]

This new "understanding" is mostly superficial. It's the first direct imaging of this process in real space. This process has already been watched in reciprocal space, which gives more physical information about it. This "pre-melting" liquidlike behavior in a solid can't be too new, since it's how we began our discussion of melting several years ago in grad thermo 101.

This is definitely worthy of a journal paper. On the other hand, it's not a paper that many physicists will be too excited about beyond appreciation of the pretty pictures.

Did nobody mentione that...

[teknokracy]

Melting happens when you open the Ark of the Covenant. It's pretty cool and liquefies your skin first.

Global Warming

[Ranger]

Global Warming causes ice to melt. Duh! Who posts this crap? Next they'll post a story about why a watched pot never boils.

You heard the one about the Southern gentleman in a northern bar. He says to the Yankee waitress: "Excuse me Maam, I'd like a piece of ice."

A short while later.

"Well thank you, maam, but my drink's still warm."

And if you don't get it, you have never heard a southerner say the word 'ice'. It rhymes with bass. Oh and people in Biloxi, MS think anyone who lives north of I-10 is a damnyankee.

In case you didn't get it...

[Spy der Mann]

The most terrible spell of all (ICE-9) :
http://www.nuklearpower.com/daily.php?date=041028

Here's how it works:
http://www.nuklearpower.com/daily.php?date=041125

And seen in action:
http://www.nuklearpower.com/daily.php?date=041102

Re:In case you didn't get it...

[indianajones428]

Actually, I believe he was refering to the fictional state of water described in Kurt Wagner's book Ice-9 (a.k.a. Cat's Cradle), which would freeze any and all water molecules it came into contact with, potentially all water on the planet (obviously an influence for the comics to which you have linked). It appears, however, that there is a real ice IX, but fortunately it won't kill us all (at least, not in the way Kurt Wagner invisioned).

Re:In case you didn't get it...

[Scarblac]

You mean Kurt Vonnegut . Strange error to make in a correction :-)

Important experiment I'm about to conduct

[Anonymous Coward]

Will ice melt faster when straight whiskey is poured over it, whiskey and water or just straight water?

why ice turns to water.

[Anonymous Coward]

As I remember ice is always ice, that is to say no such thing as 33 degree ice, likewise no such thing as 31 degree water (pure).
The ice changes to water when the level of caloric heat increases past a given point.
Ice will continue to absorb heat until enough heat causes the H+ crystalline bonds break off. This is not a quick change, a large amount nust be added, to have phase change.
This alsp applies to liquid water to stream vapor.

http://www.ac.wwu.edu/~vawter/PhysicsNet/Topics/Th ermal/PhaseChangeWater.html
Nice graphic.

Jessup

Dancing water

[Clock Nova]

This reminds me of a similar effect that I often observe while cooking, particularly while stir-frying (or any other high-heat method). That is: a drop of water will evaporate more quickly in a pan on medium heat that it will in a pan on high heat.

The reason? When a drop of water hits a pan on very high heat, the underside is instantly tranformed into a layer of vapor which then acts as a buffer between the pan and the liquid on top. So insulated, the water droplet will then "dance" and roll around the pan like a ball bearing. The drop can remain in the pan for a surprising amount of time, though I have never personally measured.

Re:Dancing water

[StarDrifter]

Its called the Leidenfrost effect

Corollary

[EvilMidnightBomber]

If "pre-melting" truly begins at the defect sites, it would be interesting to see whether ultra-low defect containing crystals melt at a higher temperature. Say, purify and grow a chunk of ice through the same procedure used to fabricate semiconductor grade silicon (Czochalski style or epitaxially), and then see if it holds together through warmer temps.

Re:Corollary

[Anonymous Coward]

Don't be silly. The entire surface, at least, is a defect. Besides, these are all kinetic effects. Thermodynamically, ice is not stable above 273K, and that's that. Doesn't matter how defect-free you make it, that just means you could maybe superheat it a bit, for a while.

Re:Corollary

[TeknoHog]

The entire surface, at least, is a defect. Besides, these are all kinetic effects. Thermodynamically, ice is not stable above 273K, and that's that. Doesn't matter how defect-free you make it, that just means you could maybe superheat it a bit, for a while.

This is a very good point which deserved more than 0 points :)

I was also thinking about supercooling: for example liquid raindrops at sub-zero temperatures, that don't freeze because there are no impurities (such as dust) to provide defects. It's a well known phenomenon and the case of superheated ice seems quite analogous.

Re:Corollary

[strikethree]

a "perfect" ice cube would melt at all points instantaneously if heat were sufficiently applied. if heat were not sufficiently applied, then uneven heat distribution would create "flaws" and the melting would start from those points.

strike

And next on Slashdot ...

[Anonymous Coward]

A ground-breaking documentary: See Grass Grow!

To be followed by a three part series on How Paint Dries! Now you can watch in real-time!

(I mean come on, it's Friday and I'm home drinking stout, but what excuse do the editors have?)

What?

[sp00nz]

it melts to match temperature. Everything does this. Why are they acting like this is new?

Re:What?

[Legion303]

"They've known the basics, but the details remained elusive."

There you go, champ.

One mystery solved and one to go

[chemacguevara]

I can't wait until they solve sublimation

Next on Slashdot.

[ciroknight]

How grass grows, the scientific miracle!

Re:Next on Slashdot.

[Anonymous Coward]

How grass grows, you say? Why, intelligent design!
Oh, how? Puff of smoke. Case closed. No further questions.

This is as much fun...

[Doolspin]

As watching grass grow.

To re-state Jeff Foxworthy's question...

[Hobadee]

...Ok, so who really cares about ice melting. Here is the bigger question: Why doesn't Jello melt? It's the only liquid that when put in the fridge, turns into a solid, but when taken out doesn't turn back into a liquid! WTF, mate!?

Re:To re-state Jeff Foxworthy's question...

[arkhan_jg]

Well for a start, jelly (or jello for the US) is solid at room temperature, or what do you think comes out of the packet?

You dissolve it in hot water (which breaks up the bonds holding the gelatin together) then put in in the fridge to cool it back down quicker... BY stirring as it cools, the gelatin molecules get tangled again. The water is left trapped between the long gelatin strands once it returns to being solid. The water is what makes it wobble.

Re:To re-state Jeff Foxworthy's question...

[cybertears]

i've expierences jello shots that have been sitting out for awhile... they are less than solid, but still yummy

pedantic, but...

[Anonymous Coward]

Aluminum. Several hundred tons of aluminum. Planes use very little steel. It'd actually be kind of interesting to have an engineering challenge about making planes from steel. Like the human-powered helicopter or concrete boats.

Re:pedantic, but...

[Col. Bloodnok]

Aluminium alloyed with copper (and other metals) actually.

http://en.wikipedia.org/wiki/Duralumin

Human powered helicopters are cool, but what's hard about making a concrete boat? Mixing the concrete probably...

You've got it wrong..

[Anonymous Coward]

Yoda, not Yodh. He's using the Force.

Slight tangent into cryogenics.

[Anonymous Coward]

Okay - so is this not a related problem to that of cryogenics (where one of the biggest problems is crystal generation due to slow freezing?)

It seems to me that recently a large number of the pieces for workable human cryogenics have started to fall into place. The astonishingly brazen (and amazingly logical) recent research into saline cryogenics goes something like: oxygen keeps things alive but also causes decay once dead - flushing a creature's blood (the source of oxygen) out and replacing it with a saline solution (that can be liquid colder than water) preserves the organism - and it can be reanimated after two hours with no ill effects.

So wouldn't the next step to be flash-freezing an entire creature? Replace the blood with saline, pressurize the body being frozen, reduce to under 0 degrees C (or whatever the freezing point of saline), then reduce pressure and "bump" - freeze everything instantly? Sure, it would take some serious nerve to volunteer for that one ("hi, we're going to extract all your blood and freeze you") - but it seems almost obtainable with today's technology.

Which is where research like this article comes in, trying to understanding the thawing process.

It seems like the "endgame" - ie: preventing terminal death - is far more obtainable than actually fixing what's wrong with a person's body and extending their life. We've almost figured out how to turn people on and off - but not how fix them so they won't permanently expire if their own devices. That needs to come next. And fast.

I may be grasping at straws, but I have a very strong desire for my runtime to extend beyond my otherwise "natural" lifespan - I'm already nearly 30 years old and starting to panic about being at the halfway point.

I'll happily have my conciousness implanted into a floor-cleaning or trash-sorting robot in 2000 year's time, so long as I'm still alive, not a total slave and have some rights as an "ascended" being. I'd like to have my own thoughts, own real property and assets (or virtual like a nice Matrix or Second Life - even if real items are capped because of severe population problems), I'd like to associate, communicate, create and socialise with whoever I wish over the hive-mind internet. It'd be nice to have an occasional weekend off for recreation as well.

Not much of a future life for living? But you'd get to see the future. For real. It'll be like a chapter of Planetary - exploring and documenting the strangeness and joy of ourselves through the eyes of a time traveller.

It could also mean that today's humans become tomorrow's robots. This could be how we achieve sentient robots - by making hardware that replaces our wetware, then transfering aging humans over to it. Not everyone would get to be jet planes and spaceships. Some would drive cars, some would make things for the humans, some would become domestic appliances. But I'll sweep floors on the moon in 2000 years if it means I'm not dead.

What's Next?

[Venerable Bede]

Watching paint dry?

Next on slashdot...

[Anonymous Coward]

how paint dries!

Cool

[Doc Ruby]

OK, how does "ice wouldn't melt in your mouth" work? Give it to me smoove, now.

Ordinary things are difficult in physics

[geordieboy]

Reading many of the responses to this post, along the lines of "Well, Duh! Big deal", reminds me of one of the frustrations of studying physics. You go in hoping to understand the mechanisms of, well, everything, and end up discovering that many things ordinary people think are simple are really terribly complex and ill-understood. My mother is not impressed that I can compute the specific heat of a degenerate fermionic gas. If I knew why water boils maybe I could convince her my education wasn't just a load of academic waffle. (Yes, I know it's a phase transition, but it's not understood fundamentally any more than melting).

Re:Ordinary things are difficult in physics

[coopex]

Just ignore those fools, they weren't impressed with my physics knowledge either, but once my Death Ray is complete they'll be sorry. Oh they'll be sorry. /me rubs hands together greedily.

Happy, pink, sunshine, kittens, love, KNIFE!

[Anonymous Coward]

There's these guys, right?

They put post-it notes on glasses of water in the freezer with words like "Happy" and "Pink" and such. All lovable positive emotions. So in this study they found out that when treated with good vibes water crystal structures are all pretty and fractal and crazy.

But when they put much, much darker words on the liquid, it responded with deep murky grey fuzz.

So in conclusion... ?

ice is warm, no cold, no warm, yes warm, no really

[djbesser]

ummm, the WARMER drink can't keep the FREEZING temp of the cube, so ummmmmm.......

i sure hope they asked rocket scientists this one.

it's not april 1st right?

SHA ZAAAAM

Mod Original Submission Funny

[DynaSoar]

"Ever wonder how ice melts? ... An understanding of how it works is crucial to gaining a _firm_ _grasp_ on the physical world."

"Grab ahold of that ice!"
"I can't! It's slippery!"
"QUICK! Somebody do some SCIENCE!"

This just in....

[Hydraulix]

News flash!! Still no cure for cancer, but scientists are hard at work discovering how ice melts. Quick somebody start polishing that noble prize!

Buy her a drink, or tell a joke...

[PoorLenore]

...that's generally how I get the ice to melt.

Quick someone...

[3seas]

patent it and make it GPL so we can all still have metling ice to cool our drinks.

Resolidification and molecular modeling

[SeanAhern]

This isn't exactly a simulation of melting, but it does involve simulation at a similar molecular level. The work that Fred Streitz and co. at Lawrence Livermore National Laboratory are doing explores the processes involved in the rapid resolidification of tantalum. They're reproducing, from first principles, some basic materials results like grain boundaries and such. It's one of the largest (if not the largest) simulation running the the world's largest supercomputer. One of my team members is doing the visualization work for it.

It shows that what many may consider to be a very simple process that is well explored and understood at a high school science class level is actually a very complex process when taken down to the molecular level. There is still a good amount of science to be done in the fundamentals of materials modeling. See this for somewhat related work and some cool pictures (if I do say so myself :-).

I like water

[ta ma de]

There is nothing like a little hydrogen bonding to get the morning started.

125 big questions

[goombah99]

make that 124 big questions..

Tea melts ice.

[Kashell]

It's obvious why ice melts. But the British would have a much better answer than I could give you.

why I don't read /. science posts any more

[museumpeace]

"...fundamental structure of matter begins to crack..."
The fundamental structure of matter? That would be subatomic physics. Ed.s: please get someone with a science background on board!

implications?

[shokk]

A premelting occurs in spots where atoms within solid crystals are not perfectly aligned, and they begin to move. The changes are seen in pictures taken as the material was heated. The imperfections are much like the differences seen in wood grain, the scientists said.

"These motions then spread into the more ordered parts of the crystal," Alsayed said. "We could see that the amount of premelting depended on the type of crystal defect and on the distance from the defect."

Does this mean that solids that are more crystaline will have a harder time melting, since there is no "pre-melt" in non-imperfect areas of the solid?

Does this also mean that because there are areas that are melting before the melting point is reached in these weak-crystaline areas, that the strong-crystaline areas are acting as insulation?

Re:implications?

[Lord Duran]

Well, what it probably means is that you need more energy to melt the more stable ones. Higher melting point.

Next massive scientific experiment!

[Lithgon]

Ice freezing!

Things we always wanted to know

[Anonymous Coward]

Next - how paint dries!

Comment removed

[account_deleted]

Comment removed based on user account deletion

a rarely considered phenomenon

[Anonymous Coward]

I'm not sure I think there's anything mystical going on in regards to melting ice cubes in drinks. The atoms in the ice cubes are simply moving faster because the liquid is warmer than the ice.

When atoms move slower they become solid. All types of matter have different boiling points, and natural liquids have lower ones while natural solids have a higher one. A natural liquid placed in refrigeration becomes a solid because the thermal excitation of the atoms reduces and the atoms begin to slow.

When they start to move faster due to heat they become liquid, and when their speed exceeds a certain threshold, they become gas. And, when the atoms in a gas exceed yet another threshold, they become plasma.

A rarely considered phenomenon that I think should be concentrated on is when the same fluid that is already in the drink is instead poured over the ice cubes slowly, it results in the ice cube melting extremely fast in those areas struck by the fluid.

how about Snapple?

[Pollardito]

ever wonder how Snapple melts?

Figure it Out..

[u16084]

Daily articles on Super computers, nano tech, new bandwidth records, speeds etc but cant figure out how ice melts? I'm going back to the mountains.

waste of money

[memnon]

Melting is considered a basic phenomenon in physics. An understanding of how it works is crucial to gaining a firm grasp on the physical world.

they only say that to try and justify wasting a lot of money on something pointless. Yes ice melts in our drinks we don't really need to know why, it just does that. spending money research like this and other pointless stuff i the reason we haven't found a cure for cancer and hiv/aids yet pisses me off

Why so sudden?

[redelm]

Freezing/melting _is_ an interesting question. Why the h3ll does it happen so suddenly when the energy distribution of the molecules has hardly shifted at all? Then there are the known but puzzling phenomena of subcooling and superheating.

Melting and materials science

[phrackwulf]

The underlying point here is the techniques materials scientists normally use to examine material properties. Techniques like FTIR, SEM, STEM and x-ray diffraction work well on materials in one state but any time phase change occurs they are too simple to examine the change as it occurs. Even an environmental SEM that can examine certain materials at higher temperatures tends to still be too simplistic to examine a phenomena like melting closely at the atomic scale. For melting energy really one of the few useful techniques is DSC (differential scanning calorimetry) and that still won't let you observe the melting mechanism itself, only detect the energy needed to reach the melting point. In this area, the physicists actually have us beaten because they at least have particle detectors that can observe the effect of high energy collisions at the sub-atomic scale. That's why this experiment is important, they are developing techniques to circumvent the limitations of the instrumentation.

Ah, memories of highschool...

[Hannah E. Davis]

Argh, this article is giving me flashbacks of all the consecutive years of "See Ice Melt!" chemistry labs in highschool. Every year from grade 9 through to grade 12, we were given the exciting task of putting ice in a beaker, measuring its temperature as it was slowly heated, and then drawing the cute little graph. And every year, we discovered that, surprise surprise, the results were the same as they had been the last time we did the lab.

Now, on the topic of the article... I'm not sure how this reflects on me as a geek, but my first thought was "Ooh, pretty pictures!", followed eventually by "Hmm, I wish I'd learned this instead of doing boring labs and watching Senior Physics videos."

I also had a teacher who'd do what he called "the water molecule dance" where he'd show the difference between solid, liquid and gas by... well... dancing. I wonder if he'll modify his dance at all if he reads about this study....

I Didn't Read the Article...

[eno2001]

...before posting this.

I'd always assumed that it had to do with transition from one state of matter to another. Water as a solid is ice. Once the temperature starts warming up above the freezing point the density of the matter decreases. There's no mystery in that, because it's what all matter does when it changes state. So... where's the mystery?

how in hell

[Anonymous Coward]

did that get modded insightful?

Why would anyone mod that up?

Also...

[MacDork]

b. These guys took this problem because "the earliest phase of melting has never been seen" but they didn't do that either! All they did was make "see-through crystals that are like small beads and are visible in an optical microscope." Doesn't sound like a hell of a lot of progress to me; anyone care to elaborate?

The article did not mention whether these crystals were polar like water molecules. I'm sure that should make some difference when we're talking about the crystalline structure of H2O. I'd also like to know if they can elaborate from this observation to explain, more effectively, why ice skates work or why avalanches move so fast.

Wrong.

[Anonymous Coward]

Actually, according to the WorldBook via START, "The temperature on Earth varies from -130 to +140 degrees F (-90 to +60 degrees C)."

Coldness.

[Grendel Drago]

If they don't have much heat capacity, then they'll warm up quickly, and be kinda useless. Water can draw considerably more heat out of your body without heating up as much.

Plus, if it's dry out, the water will evaporate, and you'll lose more heat that way.

--grendel drago