Science Doesn't Understand How Ice Forms
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- Опубликовано: 30 апр 2024
- What starts off as a simple desire to get a macro shot of a droplet of water freezing quickly leads George to the very edge of scientific knowledge and a shocking fact about most of the water on Earth.
Note: in the droplets I’m freezing, all the dendrites would have likely come from a *single nucleation point, not multiple ones.
#clearice
#waterfreezing
#nucleation
#freezingpoint
#macro
#macro4k
#macrophotography
Credits:
Executive Producer:
Matthew Radcliff
Producers:
Andrew Sobey
Elaine Seward
Darren Weaver
Writer:
George Zaidan
Host:
George Zaidan
Scientific Consultants:
Brianne Raccor, Ph.D.
Michelle Boucher, Ph.D.
Sarah Brooks, Ph.D.
Tom Whale, Ph.D.
Executive in Charge for PBS: Maribel Lopez
Director of Programming for PBS: Gabrielle Ewing
Assistant Director of Programming for PBS: John Campbell
Reactions is a production of the American Chemical Society.
© 2024 American Chemical Society. All rights reserved.
Sources:
docs.google.com/document/d/1Y... 
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The distribution of bubbles and impurities in a piece of ice can potentially tell you a lot about how it froze. So if you look at the ice cubes in your freezer, are they clear on the outside and cloudy in the middle? Clear on top and cloudy at the bottom? Uniformly cloudy throughout? Tell us what you find.
Cloudy at the center, to avoid water degassing in the solid/liquid interface it should be circulating to a liquid/gas interface like naturally happens in rivers
The question is, does that quick freeze has to do with surface tension. Maybe if you put dish soap, the droplet won’t be able to quick freeze
RUclips makes no sense. This is one of the best science channels, has nearly 500k subs, and nearly all these videos have only a few thousand views.
Lol this is not one of the best science channels. And often the science they are talking about is very very basic. Much more basic than you'd expect from the American Chemical Society, who actually publishes a substantial fraction of all chemistry research
no it's not.
yeah, algorithm kinda sucks sometimes😢
@@jogandsp It is targeted towards a general audience. Presumably, the American Chemical Society realizes that not everyone is already a chemist and wants to grow the field by getting people interested.
That's how it works, not everyone jumps like a dog the second a video is posted. Stop trying to get sympathy likes.
There's big dollars being spent on trying to minimize lithium dendrite formation in batteries!
If you're willing to go insane filming water freeze just a little more.. at 6:57 your droplet appears to be forming the tiniest ice spike ( in fact, the drop is taking on more of a conical shape as it freezes). Could be a good short, or could be a good follow-up video 🧡
I agree. The whole video is awesome, but that single shot was awesome
Looking like a cintamani
I thought I knew ice till I moved to a place that was very cold for a long time. At which time I discovered that freezing water in a freezer is nothing like it freezing outside. I've seen 3" ice crystals form on the branches of pine trees. Ice completely coated the tree in large ice crystals making the tree look like a white crystal tree instead of a pine tree. This tree was discovered during a long period of very cold weather with little to no rain or snow. When water freezes in soil or on a river. the top layer freezes then the trapped water escapes to immediately freeze. This water forms crystals that come out of the ice or push up the ground several inches. I've observed water frozen inside ice under pressure will escape to form amazing crystals. I've also observed ice forming from humid air or when ice first freezes it's in a very beautiful pattern and form. Ice forming on a body of water with changing heights is also very interesting. On a river that's freezing the top millimeter may freeze then vertical walls start to freeze and work downward. If the water level lowers during this time these pockets of water will drain out and the result is a very rigid hollow structure of ice with pockets 1-2 inches deep. The ice walls that formed are all straight lines that form perpendicular to the ice crystals on the surface. Which end up with perfectly straight walls of ice 2--24" inches length. When ice first freezes on a river a thin layer of ice forms with the crystal shapes that you observed, some may be very long in inches or feet in length. As more and more ice freezes those crystal shapes become less visible. In a river the first freeze is crystal clear as the impurities are carried away by the river. Even several inches thick it's perfectly clear an looks like one is walking on water. The only way to tell the depth of the ice is by finding a crack. The ice often has cracks or holes where pockets of water were trapped and then froze pressurizing the water and forcing it out freezing in crystalline shapes.
I think that ice has a very beautiful crystal shape, but it's very fragile so we rarely see it. Which is why it's seen at first then goes away over time. Only in the right conditions do the crystals remain or grow.
To try to see crystals form fast or slowly. Setup a flat surface such as a pane of glass vertically. Then freeze the vertical pane and slowly expose it to humid air. The moisture in the air will attach to the first ice that forms and grow in beautiful patterns from that point.
I noticed the snow and ice are different in Washington State and in Massachusetts during the winter... On the west coast the snow is more clumpy.
Makes me wonder if the reason why the dendrites are never the same when refreezing is because the environment within the water and ice is both changing and moving. We don't see the molecules flying all around is or even get a sense of the world rotating and revolving around the sun ultimately causing the ice to form different shaped dendrites.
Horefrost! (I don't think that's how it's spelled...)
Basically the air itself freezes, so the moisture falls out of suspension and clings to what's close. You can get those biggies after fog too. Sometimes the fog is from the exact same "moisture falling out of suspension" reasons.
Water is such a fascinatingly strange fluid, yet because it is so common, we assume its behavior is typical. Great video. Thank you for sharing.
Theoretically, if the water was touching a perfectly flat surface, it probably won't have those dendrites shooting up from the bottom.
Ya, thinking of chemist trying to form a molecule, scratching the surface of the beaker to form a nucleation point.
Yep. Homogeneous vs heterogeneous nucleation.
I think the issue there is that the idea of 'flat' doesn't exist very well at the molecular scale. Even something like a graphene sheet isn't perfectly flat at some scale it will be 'rough'.
I think it has something to do with differential hydrogen-like bonding that allows for a quick nucleation site. And that's a bit difficult to predict the 'exact conditions'. on that scale.
My observation has been the opposite. That water freezes in the dendrite crystalline form first but it's so fragile that form only remains in the right conditions. Try freezing moist air with a very cold pane of glass where on one side its 0 degree F and the other is 35-40 degrees with some humidity. The humidity attaches to the first ice that forms and grows from that position. The rate of growth can be controlled by the humidity in air. I've seen very slow growth stay for several days.
I love how the shape of the drop changes as it freezes
Levitate some pure water in a magnetic field (like with the frog) and freeze it? Make the pure water in a vacuum chamber by vapour and then trapping the vapour in the field?
Not going to lie, kinda expected Alex for this one. No shade on George, I love them both.
Yes, I also expected at least some comments from her
Wish there had been at least one zoom in on the little ice tree escaping from the tiny tip of the droplets.
I tried to capture it at 5x magnification but couldn’t! I’ll keep trying…
Just discovered this channel and... man... this is what internet should be for! Amazing work! Congratulations!
Appreciate ya. Thanks for sharing.
I found everything in the video to be interesting and informative. Thank you.
Here for the algorithm, because this channel is due fir a blow up! 😊
Fascinating, very good explanation, thank you!
Water droplet turning into an onion dome was unexpected! So pretty
guessing at 9:00... it seems like the droplets are super-cooling at the bottom, and the dendrites form when the first crystallization starts. When you "bumped the table at the wrong time", it's possible you actually _caused_ the dendrites to form.
That was super interesting. Thanks!
Great video of the droplets. I can only imagine how difficult it would have been to get those shots.
@stevemould inspired 2D model there? Really fascinating video, thanks.
Yes we do. The water molecule seeds on the impurity and builds a structure from it. It will grow exactly like a snowflake does, adding molecules of water along the lines of hexagonal structure. It is exactly why it's never the same.
Water freezes in most natural situations on earth as a propagating hexagonal structure that started at a not water seed ... whether that was dust, pollen, sodium, or an irregularity on the surface of a glass
Maybe the dude is called Science and the title of the video is about him not understanding how ice forms?
Now I want to do this, but with an electric field to nudge the little wiggly dipole bois towards alignment as they freeze. Or maybe a varying field, to see how that affects things.
Bartenders use insulating containers like vacuum flasks to make crystal clear ice. Freezing begins from a point where it does not touching anything and pushes impurities out, then you get rid of a part with impurities, and voila, clear ice, no dendrites
Take it to the limit... one more time. Thanks again.
What you are seeing as it starts to freeze is the result of electrons being lost in the water where it's freezing. The electrons are forced away from the cold (up). It happens very fast at first due to the amount of electrons in the warm water.
Great work
Those "mistakes" you made weren't at the wrong moment, as in, they didn't coincidentally freeze at the same time. Your actions initiated the crystalization process. What you theoretically talk about in this video is called the homogeneous nucleation process. This happens in ideal conditions in the absence of impurities. But in reality heterogeneous nucleation is more likely. The shake and the laser beams could have caused a pressure/temp difference that create a nucleation site.
(1) Water expands when it freezes.
(2) is your test surface ultra smooth? If not, I'd say the dentrites form in a "cavity" (void)...where it takes less energy for the water to expand...into ice.
Thanx for insight
What if... You shine a laser beam, a very small one, at the dead center of the droplet, how would the freezing of the water be affected? Would it allow a spot right in the center where the beam is to freeze much slower, resulting in an escape hole for air?
The drops on the table get dendrites started by the seed crystals that are on the cold plate. All it takes is a few molecules that get jumbled in the right orientation to start a seed when they are cold enough. If it’s still (non-motion) enough, that’s how you can get supercooled water but it only takes a small bump to get the cascade freeze. This is really not understood?
The slo mo guys should help you get the perfect shot!!
That was awesome.
Van Der Waals forces, sound, any disturbance which can cause locally super cooled water to nucleate will form a dendrite. At the smallest scale there are still currents and Brownian motion. All it takes is a pressure wave of any kind to tip the balance and cause a cascade...a.k.a...a nucleation event leading to dendrite formation. And yes, science does understand how ice forms.
So, I’m going to walk out onto a dubious limb and mention that the texture and other properties of the surface the freezing on are generating nucleation sites that seed the dendrite formation by having some attractive property(or properties) for the water to more easily build the ice lattice. Maybe it’s a heat draw thing; maybe thermal conductivity has nothing to do with it.
My point: what would happen if you froze the water on Teflon?
…or some other surface that is hydrophobic?
A good, smooth, hydrophobic surface is going to probably be as close to not having water in contact with a surface as you can get without going to space.
You probably need to have some kind of dimple or concavity to prevent the droplet from running off; but I’d love to see the video, to see if the dendrites from differently from these experiments.
Also: slow motion cameras!
Think ice dendrites are cool?
Wait until you’ve seen them forming at 10,000-100,000 fps! 🤓
Talk to The Slow-Mo Guys. They might be willing to collaborate.
Seems like the impurities act like nucleation sites, similar to raindrop/snowflake formation or soda bubbles. Chaotic.
Freezing water won't freeze until it has a nuclei. This allows a temperature based pressure to form and "explode" when the threshold is crossed causing a sudden expansion of ice, and then a linear expansion.
We have very different definitions of crystal clear.
I bet certain molecules, when present in water that is just about to freeze, and given the wide range of possible circumstances, will turn out to be able to build “backbones” or templates for more complicated molecule structures, assembling them while freezing, letting them go when melting, eventually even peptides and beyond could start forming, starting the chemical evaluation that led to the formation of the very first multiplication ready cell(s). Should I be a chemist with free time, I would definitely try to add such molecules to freezing water that are needed for biomolecules, and see if I can start getting any kind of surprising result. It would probably require an industrial number of droplets with changing speed of freezing and relative amount of chemicals. This experiment might even give a more tangible result than the Miller-Urey one with all that boiling. I claim half of the Nobel prize money, by the way.
It's so surprisingly violent... kinda like an explosion.
So it's not the water that's touching the coldest surface, freezing, and quickly floating up because the density is too high at the bottom?
Just takes a little bump to kick off a nucleation site.
YAYYYYY ANOTHE R ICE CHEMISTRY VID YIPPEEE ICEE NICEEE !!!
But why/how water freezes at 0 deegrees Celcius? It has to do with the energy levels at taht specific temperature. Something happens at that temperature that allows chemical bonds to occur, thus the lattice. Tight binding? Does it have something to do with the atomic orbitals? Their energy levels???
Hey, it's the gas mask guy.
Sup
you need to talk about the onion domes
How is ice formed?
They need to do way instain water.
But you forgot to mention what is going on at the very top of the drop as it freezes, and how it changes form. Seen at 06:57
Yes! Tried to get ultra close up of those but ran out of time - next vid maybe!
Dendrites form due to supercooling and lack of nucleation centers at initial point. Once some heat is released due to dendrites formation, and water reaches equilibrium 0 degrees, everything goes normal.
And the statement that impurities help the ice to form at temperatures above 0 (10:17) is simply wrong. Impurities always lower the freezing temperature. Not only for water, but for any other liquid. It’s a well-known principle of cryoscopy used to measure molecular masses, dissociation constants, etc.
Good, we did not need another video on clear ice.
At the top of the drop as it freezes trough, something interesting is happening.
Eeyy it's that guy again, sup guy 😄
Imagine if Antarctica were clear ice
Error in the captions: "thawed" was transcribed as "thought" (more than once).
Thanks for the heads up! It's been updated.
@@ACSReactions Cheers! Happy to help.
as the water gets sub zero celsius, it kinetically slows down. Isn't the first "proper orientation" hydrogen bonds of the lattice just a statistics game averaged out over trillions and trillions of individual interactions? That would explain why it never freezes the same way twice.
(06:54) something cool and strange happens at the top of the droplet :)
its looks to me its choosing the path of least resistance
Try freezing a distilled water droplet floating in space?
This Answer (along with a multitude of other scientific quandaries) is obvious, but only if you reprogram your mind to access cosmic data banks like the Akashic records..
ice crystals exploded into the drop?????
Call the Slow-Mo Guys they will get your shot.
Yes it does... Science is fully aware that if you put water in a freezer, it forms ice! 😂
That's always another why.
except saltwater (sea) does not freeze. neither does high grade alcohol, eventghough still has water.
Science doesn't understand how most things form
Acyl-butenol, definitely *not* a dye
❤
Whats with the piano hands? For this listener, theyre distracting.
VUQUUM the air
Science knows exactly how ice forms. Video not worth watching with that title
well, why aren't scientists finding out then? this seems like something that any decent phd candidate can study with the right equipment?
Maybe don't believe video titles on RUclips.
You definitely shouldn't just believe titles, you should watch the video, then check out the sources in the description.
And a lot of scientists are working to figure this out. It's rather difficult.
@@ACSReactions when a rando assumes i didn't watch the video, nobody cares. but i definitely finished the video, which is why i'm asking this exact question. it is extremely obnoxious for the creator to make such an assumption when there is literally nothing in my comment that would imply i didn't watch the video.
you demonstrated all that footage about dendrites forming and then said "nobody knows why they form" which seems completely weird since we DO know they form and we can even narrow down the conditions for which they form. we even have slomo footage etc... so the logical next step is something like electron microscopy perhaps? more better footage? that's purely from observation; which is why i said phd candidates, since they're more numerous and can be tasked to do these more repetitive tasks.
some of them did a ton of work to photograph droplets of water in the air just to understand how raindrops form and how they fall through the air... which seemed almost whimsical and frivolous; yet it greatly advanced our understanding of how rainstorms work, how hailstones form, how to reinforce roofing material to withstand it etc.
understanding dendritic formation could further advance our knowledge on freezing applications, maybe improve the efficiency of freezers or help figure out the optimum conditions for cryo preservation with minimal damage.
it's actually a serious question.
@alveolate Oh yeah, sorry, I was agreeing with the other commenter that you shouldn't just blindly believe titles on RUclips, didn't mean to imply that you hadn't watched. And I meant to give you a serious answer, that many researchers are looking into this, but it's a very difficult thing to nail down.
Apologies for the poor phrasing!
@@alveolateYeah, it’s an incredibly complex question, and the variables are very hard to isolate, since we’re talking about atom-by-atom variations having macroscopic effects. There are even dozens of KINDS of ice, some of which have only been discovered in the past year.
Temperature drops, water gets cold, ice forms. Simple. I'll take the funding for all the expensive studies thanks 😂
It forms by freezing. DUH.
dont worry, God knows, so you dont have to know anything, or trying to figure out the laws, of anything. God takes care of you, not you yourself or your science physics laws. honor to the Lord.
"Science Doesn't Understand How Ice Forms"
Duh, when water gets cold enough it becomes solid and that's ice.