Why does ice float? - Forces of Nature with Brian Cox: Episode 1 - BBC One
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- Опубликовано: 27 июн 2016
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Watch the BBC first on iPlayer 👉 bbc.in/iPlayer-Home Programme website: bbc.in/29kGs3z Ice is the only common solid that floats on its liquid form. But why? Professor Brian Cox explains it's all down to a hidden force of nature.
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Brian cox is such a cool guy.
He explains so nicely, I just love this show
When I was a kid myself and my dad were watching a really badly made 1950's movie on TV about a submarine in the arctic... in the middle of the movie the ice above the sub cracked and ice fell onto the submarine....
At that point I said... 'doesn't ice float.?.. how is it falling on the submarine?' and he said 'Shut up, the movie is crap enough without you and science having a go and all!'
Clever man my dad!
wow, 'you are so smart' good for you
was it really bad movie? they forced ice to fall in water. special effects right there
Well, it depends... If the ice fell from a higher point it could temporarily fall down a little before floating back up, but my guess is that isn't how it was in the movie.
If only Brian Cox had of been my science teacher. I just might have been interested.
same
Very inspiring! Perhaps Raman spectroscopy could provide real-time data and further insights into these chemical processes, in addition to drying paint.
Amazing... Love you Brian ❤️
Phenemonal info, and awesome presentation thanks 🤙🏼
Brian Cox was fantastic in the band D-reem. He is brilliant has a scientist.
Excellent
Best example of simple scientific explanation!!!!
Very cool. Thanks
i have always wondered about this.
the first answer i got was its because of "anomalous expansion of water".
I went on to ask why did water have that property..
only today after watching the first episode i got a beautiful answer...
Amazing. 👍
Can someone please tell me the name of the music played at the very start and the very ending while showing the BBC Logo
Water is amazing
I don't think he explained as well as he could have. The hexagonal grouping of the (frozen) water molecule is less dense than (unfrozen) water molecule allows water to float as a solid on its liquid version. I think that's the take-away.
1:05 "positive charges can attract other negatively charged ends of other water molecules..."??? That's just confusing.
I disagree: it seemed very clear to me. It's obvious that the same number of molecules of any substance with a crystal structure (hexagonal or otherwise) will occupy more space than a non-crystal structure, as liquids are. Because there are fewer atoms in the same amount of space, it's lighter. Seems clear enough to me.
Read your comment to a friend who's not a scientist and then ask them if they know what you're talking about.
il barone I'll be the "non scientist " and I understood it.
But it maybe it's a language thing too. Dense, in science, is another word for weight. And everyone knows that, light things float on heavier ones. Can anyone give another example, of a solid form floating on the liquid form of the same substance? The only ones I can think of , have a large water content.
to be honest i am not a scientist but i like to watch, and i don't understand until i read ur comment thanks @il barone
nice
I hope that's not a single malt you're putting ice in!
One of the reasons I prefer whisky to other alcohol is that when I first went to Scotland and asked people there what the correct way of drinking it was, their answer was "The best way to drink it is however you like it." Taste is as subjective as you can get - why would anyone feel compelled to prescribe to others what they should enjoy?
lmao u are a man like me :
As a child I always thought you could wear water out, for want of a better phrase, by freezing and then melting it over and over again.
I thought it was going to be something simple like air trapped in it, but no 😵😰😱 haha
Hydrogen bonding and Van der Waals forces - chemistry 101.
james blunt...
Can anyone identify the coat Mr. Cox is wearing?
It looks so nice and toasty.
Here's a question: Do the hydrogen atoms "belonging" to one particular water molecule exchange places when all these individual units are hydrogen-bonded to each other into a great big super molecule, or is there a distinction between the native molecular (dunno if you'd call it covalent or ionic - I'm assuming it's the same as any other metal oxide) bond and the almost-as-close hydrogen bond with a neighboring molecule?
In other words, can individual electrons randomly migrate around the super molecule in solid or liquid water?
Great question, In ice the atoms stay as they are and do not switch places as there is not enough heat (energy) for them to move around. But in water the Hydrogens do in fact switch places between the water molecules. Some H+ fall off one molecule and bind to another making H3O+ and leaving behind a OH-. This happens in an equilibrium and is the reason why pure water has a pH of 7, as it has exactly the same amount of H+ floating around as there are OH-.
Electrons are in continuous movement and they may randomly migrate and being exchanged as long as there is also chance that electrons from other atom can be "capture" so it will maintain electrical neutrality. Now, regarding crystalline materials, this are not called super-molecules but "single crystals", where all the atoms are periodically organized and the distance between atoms is the same in specific directions. The crystals, however, are not perfect. There maybe "holes" called vacancies and in many crystalline materials this vacancies are places where atoms can jump in and out due to thermal vibration. Atoms are always vibrating even at freezing temperatures. They maybe almost "frozen" near zero absolute temperatures (-273.15 C)
I had a dream about this question and realised that the last line should have read:
"In other words, can individual protons randomly migrate around the super molecule in solid or liquid water?"
- which is how I typed it initially.
Float on.. whiskey
i would of thought it would be with like enough space for pockets of air to get it aha
Did you understand Brian Cox' explanation for why ice floats on water. Most likely not, and that is because he, in fact, does not explain why ice floats. He wants to impress you with what is a not very impressive demonstration of the unique characteristic of water, which he does not mention per se: water is a polar molecule. For those of us who did not spend the night at the Holiday Inn, as the commercial goes the implication being only smart people make that choice, ice floats because when water freezes, it expands, with the water being the only non-metalic liquid that does that. Because it expands, its density is reduced, by some 9% compared to water, which makes it float. In the end, water is kind of mystery miraculous substance, reason why TV scientists like Cox stay away from admitting certain things about it.
ok i understand from this video how water molecule is made and ice floats because it is less dense than water but i dont understand why it is less dense
Its cuz of the structure of the molecules. They are not compact they have a hexagon structure. So in the middle there is nothing. So it makes it lighter. Less dense
Why does ice float . . . Cos it went to school and became less dense . . .
I still dont get it
one day every atom on earth will have shared knowledge
Apparently they already do.
ok
why is it less dense?
he just explained it in the video
I agree it's not exactly explained very well in the video, even though I love Brain... Basically because the molecule is bent when it sticks together it binds edge to edge. Because it is hexagonal there is a lot of space left in the middle that isn't filled. Because of this it takes up more room with less molecules. When H20 is in water form it all piles onto itself every which way and leaves no "holes" in between the molecules so you can fit more of the molecules into the same volume of space, making it more dense.
thx you helped me understand it even more !!
Okay so remember oxygen has 8 electrons... hydrogen only one... which means that the hydrogen with only one electron will be very, very slightly positively charged... that means it will attract a negatively charge molecule.... IF, and only IF that molecule is moving slow enough to be attracted...but only to the hydrogen, not to the oxygen.This so has the property of making the ice as it forms a crystal with lots and lots of empty space in the middle hexagonal bit... theres more space in ice than there is in water... water is just ice with faster moving molecules...and because they move faster you can fit more of them into the space.... thy don't spend long enough in one space to be affected by the charge.
In fact thats all temperature really is,... its a measure of how fast the molecules in a substance are moving. If they are not moving at all its a solid... and also very cold. In fact totally static and not moving whatsoever...with a low level of decay then a solid is -273 degrees... absolute zero.
Water is the only known substance that is less dense at lower temperature because of this hexagonal arrangement. Hexagons are also a very common arrangement ion nature... bees do it too but in fact all they are doing is making spheres... the hexagons form because just like soap bubbles if you put five of them together the middle bit is a hexagon.
This concludes your science lesson for today... go get a coffee.
thanks a lot.. thats the best explanation so far....and in our part of the world we prefer tea...
He hasnt completed the explanation !..
He is a great communicator but missed quite bit here
watch the whole episode and you won't feel that...
as per as i think
@@wnderer4365 I'm not taking anything away from him . He is very good..but my point still stands ..I like him in either way
@@premprasad3511 did you watch the whole episode ???
@@wnderer4365 I did again after you prompted me a second time but I s the same ! He doesn't refer to the anomalous expansion that starts at 4 degrees Celsius expanding the water as it freezes..
That point is missing...
@@premprasad3511 well i think he basically told the inner mechanism of the anomalous expansion.
at from 4°C water starts to take shape of hexagonal crystal.. thus lowering the density till 0°C at which they lock in the hexagonal crystalline structure..
Can you freeze fire?
Woody Hutton, Now THAT I'd love to see!
freeze light good one
You’ll float too…..
ice floats because it is less dense than water, yet denser than air. Duh.
God did it mate. in case Noah fucked up the boat.
Where does the two nitrogen atoms come from in a water molecule? - its two hydrogen and one oxygen (mind you its been a while since I was at school)
You must have misheard, he said that water was made up of Hydrogen and Oxygen, he didn't mention Nitrogen.
+MrSabianFaz
I mis-heard - my ears must still use valve technology and hadn't warmed up........
I don`t eat ice so why my feces float ?
That's a very bad explanation only a physicist could do. The basic reason ice is floating in water is because Ice has a density of 9% lower than water and a volume of 9% bigger. In other words, when water crystallises in ice particles it expands in volume and lowers in density. Because of this, ice will always float into water.
Jeruzalem is the capital of Palestina
This guy is a textbook CGI deceiver.