Metal disk works by creating a small gap in the perforated grooves of the disk, which in turn provides the environment to create a nucleation site. You can tell if you have one of these, because the perforations on the disk become increasingly separated to the point where only light pressure initiates the phase change, and you don't have to totally invert the disk.
@@hi_im_angelatrainor from inside one of those cheap reusable click heat packs. I don't know how they manufacture it but it doesn't seem too difficult to make. Sorry I don't know what it's called exactly or how you might get a lot of them but salvaging one from an existing product is any easy way to get one if your trying to DIY your own heat pack
I requested this video, thank you. sodium acetate is incredible to me, ive made sodium acetate trihydrate a few times its just to feel ice at a physically hot temperature
Feels like forever since Prof. Bowley was in one of your videos. Great to see him back! Loving the footage from the thermal camera. Maybe a video on how they work and what limitations they have would be a great topic for Sixty symbols? (Hint hint) You would already have great footage to use, so besides talking to a professor, editing, possibly animating and uploading, the video practically makes itself!
So excellent to see Prof. Bowley back, but I'm surprised at how little air time he got. Always enjoyed his videos from before he retired. Hope there's more from him in the future!
My 8th grade science teacher had quite a few of these, only much larger. He played on an ice hockey team and needed then in case of injury. The really neat thing about large hot ice packs is that they conform to the shape of the body part and the crystals help hold it in place, so you don't have to worry about it slipping out of place if you wrap some tape a compression wrap around it before you get up and move around.
Great to see Dr. Bowley again! I love this series so much and all of the enjoyable and personable scientists who spend their time with Brady to teach us in a totally new way. Cheers!
really like the thermal imaging camera. makes watching boiling water interesting. idea: put ice/dry ice/liquid nitrogen into boiling water and see how it looks under thermal imaging.
That type of handwarmer is quite nice as it's re-usable. In one of the local shops they sell a type that from memory is made of fine iron dust and coal. Not sure if there's more to it. Seems to generate heat from oxidation quite simply. Each pack is single use and is stored in a sealed plastic bag. Quite nice and relatively safe and a couple of hours.
4:06 "So that's what you have to do to finish it off: Just put it in there, leave it for a little while - you take it out and let it relax" A strangely accurate description for many different situations in life ;-)
I have 8 of these and I take four out while cycling two in my gloves and two in my sleeves in winter and put 4 on my pillow before bed when it's really cold. Really like the Chemistry in these little things XD
I already knew this one! ;) I have 2 of these packets (blue, pillow-shapes). I was so intrigued by their properties that I had to look up Online what solution was inside and how the reaction worked. First time I ever saw something like these, were in military, back in '03, where we had both _warming_ and _cooling_ packets to treat different injuries.
Eee, it's good to see Prof. Emeritus Roger again as well! I had no idea sodium acetate was so ubiquitous (yes, I was intrigued enough to look it up). And yet, we don't hear much about it.
It's a "supercooled water instantaneous freezing" phenomena. Super clean water that is cooled to a freezer temperature needs just a nudge to start crystal forming chain reaction (which is not a chemical reaction but a physical process). Same here: pressing on the metal pushes random two particles together, forming simplest possible crystal seed and chain reaction like process forms precipitation around this crystal seed.
This was actually quite a mystery to me as well, and I think I have figured it out. Can't remember which website I read it on, but one of the companies that made this said that the metal disk has a lot of tiny grooves in it that are perforated. When the disk is inverted, the perforated grooves separate slightly; creating this cavity that you mentioned.
I bought a hand warmer like that back in the early '90s. Now when I hear about them or see videos about, I think more about the super-saturated solution, and how that relates to cooking, specifically candy making.
Those metal discs don't release anything. They create shock wave (high pressure area) that initiate crystallization. The same effect you have with very cold beer when you slam it hard against the table. Notice the second heart at 1:28 there are 3 areas where crystallization was initiated.
That metal disc does not release anything. It just creates a shockwave that propagates through the solution. That's enough for nucleation to occur. Remembe that when you have superheated or supercooled water, you also just need to tap the glass to induce state change.
I'm pretty certain the solution is simply a supercooled sodium acetate solution, the little metal disc provides a point of nucleation when bent. Allowing the solution to "freeze" at ~60c (the freezing point of sodium acetate)
I'm not finding a price for that camera on Flir's website, but the site says it's research-grade, and elsewhere I found a similar model number listed at $40,000. The optics are f/1.2 or below (depending on focal length), which is impressive too.
Fantastic footage. That camera is amazing. Brady ... question ... i couldn't help but look at the scale to the right. Seems like the camera footage is interlaced, but the scale isn't ... or vice versa?
It's also fun to pour out and make into towers and other things as the super saturated solution crystallizes as it hits the already poured stuff. Do that with the thermal camera. :)
I actually did this experiment in lab but never touched the test tube. The way to get sodium acetate crystal is intriguing because acetate is uncommon since acetic acid is weak and won't disassociate easily. Thats why I think sodium hydroxide is used, but in my experiment we used sodium carbonate!
The thin metal disk that triggers the chain reaction actually has tiny fissures throughout it. The disk is stamped out a thin piece of metal and these fissures are created by stamping the metal disk hard enough so that it superficially tears the surface of the metal. Some of the sodium acetate crystals get trapped within these microscopic fissures and pressing or bending that metal disk causes a release or exposure of the crystal(s). It is a supercooled solution.
Since you have rather nice thermal camera it might be nice to show this same effect with the bang a bottle of supercooled water on a desk to make it freeze instantly, that should also warm up as it freezes but not as much.
Sodium Acetate is also the flavoring agent used in salt and vinegar crisps. It is also fairly easy to make at home using distilled vinegar, distilled water and baking soda.
does the clicker have to release a particle to form a nucleation point? in just thinking about when you hit a bottle of supercooled beer or water and it freezes because of the shock
I have a question here.On April 17th 2009 you made a video about erbium and you said its a nuclear poison , can i use it in building constructions in order to protect it from nuclear explosions?
Is sodium acetate solution ever used for cooling systems? Although liquid metals seem to be used sometimes, nothing has the sheer heat capacity of water, and I'd expect that transfer of heat is much faster if you can use the sodium acetate to keep the temperature gradient high; while absorbing heat from machinery that needs cooling, the solution will keep itself cool for a while rather than quickly reaching near-equalibrium, then when releasing heat out into the environment it can spend much longer being much hotter than the environment using the sodium acetate.
I've got a question. I have one of those. It is activated (crystallized). For 8-10 years it layed around in that state. If I heat it up now, will it be usable?
Probably not. My experience is that if one its around in the solid state for even a few months, let alone a few years, enough water is lost that the sodium acetate can never be fully dissolved again. They seem to be more resistant to this loss when in the liquid state, but since they can "fire" accidentally, there is no completely safe way to store them long-term.
+Scott Sakurai There is no water left in it. +Harald Sangvik It didn´t work. +Scott Sakurai I have one that stayed there for the same amount of time in liquid form. Can I activate it and then put it cack in it´s liquid form? Or is it a one time use and I can´t put it back?
If it's still liquid, it is probably still usable no matter how long it has been sitting around. At least I've never had one fail that way, only from sitting in the solid state too long, or the bag tearing.
+Scott Sakurai The thing is that I remember boiling that thing directly after I used it. It didn´t become liquid again.. Now it stayed there in solid state for 8 years and doesn´t work. I´ll try the liquid one soon.
I think the clicker cavitates the water, in other words it creates a low pressure area which would contain water vapour due to the low pressure in the shockwave, and there would be a powder of sodium acetate left behind to catalyze the crystallization.
BooBaddyBig I do think that's a reasonable theory but I did, as promised above, look into this and I have really struggled to find an authoritative answer to this. The theories seem to be seeding from particles of sodium acetate or iron given off by the clicker (I am highly sceptical of this explanation), your explanation or the shock wave from the clicker pushing atoms into sufficient proximity to form a crystal. However, look as I might, I cannot find anything more than reasonable opinions and not real research. If anyone knows of any, please tell.
I've always thought it was a shock wave rather than cavitation. The first heat pack I brought said to punch it to activate it and it did not have a metal clicker in it. Also the instant frozen drink trick uses a shock to start the rapid freezing.
I prefer all of the theories here over "a piece of sodium acetate gets clicked off the disk." Especially because the end of the video basically says that couldn't be possible.
How can those degrade over time? I had some of them and after a about a year they never turn quite clear again after boiling them up. They will still activate and produce heat but they somewhat stay crystallized.
This reminds me of an experiment with clear water where you cool it down but it doesnt freez up. Then you drop an impurity or just hit the side of the vessel to create vibration and the water inside freezes .... well ... something along these lines. : )
This behaves like a super-cool solution. Water will do the same thing. If you are careful you can cool pure water to well below zero degrees. Then if you give the water a slight bump, or there is a tiny particle in the water, the entire container will freeze almost instantly. This process generates heat warming the water to zero degrees. Is this process the same thing, but with something with a higher freezing temperature?
sodium tiosulfate disolves at 55c and if not shaken can be chilled down to below room temperature. undercooled sodium tiosulfate acts the same way. temperature raises to its melting point. ref to supercolled liquid.
Lajos Winkler my bad fixed typo its tiosulfate... comonly used as fixative in b/w photography rendering process. the other interesting property dechlorination of water.
Wait I thought it was spring steel and when snapped a nucleation point forms and crystals precipitate proximally. Just like a supercooled water bottle in your freezer if slapped goes from liquid to ice... he made it sound like a chemical catalyst to initiate it's propagation. Anyone Know?
Yes. Although impurities are a problem with household versions of those chemicals. Nurdrage has a video of trying to make it and dealing with purity issues.
Since the particle is coming off of the little metal clicker, then wouldn't it have to be sodium acetate? If it was metal, then the particle would remain in the solution when it's boiled and it would spontaneously crystallize again around the existing metal particle.
One time, the package buried in the microwave(I was trying to revert it) and I didn't think of it, but after awhile, there was a white, powdery residue that smelled very similar to salt and vinegar chips.
Why doesn't the piece of metal itself act as a nucleation site? Or, if it does indeed release a tiny piece of metal, why doesn't that metal continue to float around the heart and, after fully reheating and recooling the object, immediately act as a new nucleation site?
White Autumn My girlfriend got one from one of those Pure Romance parties, that's the only one I had ever seen until I noticed this video by coincidence. It's about twice the size of the ones in this video but otherwise exactly the same.
+White Autumn in usa, if you live in cold climates, or seasonal climates, you can buy them at nearly any store. even gas stations have hand warmers and feet warmers of all sizes. i just bought some to get ready for winter.
but I've never seen them filled with liquid,'the ones here are all filled with some kind of dry powdered metallic. maybe it's magnesium? I'd like to know how the dry hand warmers work - any chemistry guys out there can tell me?
"Warmth coming in the middle of the heart. The other heart doesn't do anything." I feel your pain bro.
Lance Everett
deep.. lol
Nice molecular modelling! Great demonstration of the energy required to break bonds and energy released when bonds form.
is he using snatoms?
Fabian Huber Yes, indeed.
The creator of those must have been a real shrewd fella!
Didn't expect to see you here haha
First Vsause gets involved in the channel, now Veritasium......... is this where the cool kids hang out?
This was heart warming.
bob hoo cers get out
hur
bob hoo cers ha. Corny joke. I like it.
carefully, he's a hero
Metal disk works by creating a small gap in the perforated grooves of the disk, which in turn provides the environment to create a nucleation site. You can tell if you have one of these, because the perforations on the disk become increasingly separated to the point where only light pressure initiates the phase change, and you don't have to totally invert the disk.
Quentin Lightner thanks, that was the missing bit i wanted to know
Where do I get disk?
@@hi_im_angelatrainor from inside one of those cheap reusable click heat packs. I don't know how they manufacture it but it doesn't seem too difficult to make. Sorry I don't know what it's called exactly or how you might get a lot of them but salvaging one from an existing product is any easy way to get one if your trying to DIY your own heat pack
Outstanding video! It would have been great to cut open one of the hearts and take a close look at the metal disc.
I requested this video, thank you. sodium acetate is incredible to me, ive made sodium acetate trihydrate a few times its just to feel ice at a physically hot temperature
Thermal imaging proves that Brady is one cool dude.
TheAtheistPaladin He's got a cool nose, at the very least!
Feels like forever since Prof. Bowley was in one of your videos. Great to see him back! Loving the footage from the thermal camera. Maybe a video on how they work and what limitations they have would be a great topic for Sixty symbols? (Hint hint) You would already have great footage to use, so besides talking to a professor, editing, possibly animating and uploading, the video practically makes itself!
So excellent to see Prof. Bowley back, but I'm surprised at how little air time he got. Always enjoyed his videos from before he retired. Hope there's more from him in the future!
My 8th grade science teacher had quite a few of these, only much larger. He played on an ice hockey team and needed then in case of injury. The really neat thing about large hot ice packs is that they conform to the shape of the body part and the crystals help hold it in place, so you don't have to worry about it slipping out of place if you wrap some tape a compression wrap around it before you get up and move around.
Great to see Dr. Bowley again! I love this series so much and all of the enjoyable and personable scientists who spend their time with Brady to teach us in a totally new way. Cheers!
wow Snatoms !! Thank you for supporting Derek guys and I honestly think he really nailed it with this product !
really like the thermal imaging camera. makes watching boiling water interesting.
idea: put ice/dry ice/liquid nitrogen into boiling water and see how it looks under thermal imaging.
Another great video! I would like to request more video's on how science & chemistry can keep you warm this winter.
Excellent explanation
That type of handwarmer is quite nice as it's re-usable. In one of the local shops they sell a type that from memory is made of fine iron dust and coal. Not sure if there's more to it. Seems to generate heat from oxidation quite simply. Each pack is single use and is stored in a sealed plastic bag. Quite nice and relatively safe and a couple of hours.
4:06 "So that's what you have to do to finish it off: Just put it in there, leave it for a little while - you take it out and let it relax"
A strangely accurate description for many different situations in life ;-)
XD
I have 8 of these and I take four out while cycling two in my gloves and two in my sleeves in winter and put 4 on my pillow before bed when it's really cold. Really like the Chemistry in these little things XD
Good to see Roger again, even if for just a minute. Is he willing to do some more videos?
I already knew this one! ;) I have 2 of these packets (blue, pillow-shapes). I was so intrigued by their properties that I had to look up Online what solution was inside and how the reaction worked. First time I ever saw something like these, were in military, back in '03, where we had both _warming_ and _cooling_ packets to treat different injuries.
Eee, it's good to see Prof. Emeritus Roger again as well!
I had no idea sodium acetate was so ubiquitous (yes, I was intrigued enough to look it up). And yet, we don't hear much about it.
Very interesting video, the thermal imaging makes it even more captivating !
It's a "supercooled water instantaneous freezing" phenomena. Super clean water that is cooled to a freezer temperature needs just a nudge to start crystal forming chain reaction (which is not a chemical reaction but a physical process).
Same here: pressing on the metal pushes random two particles together, forming simplest possible crystal seed and chain reaction like process forms precipitation around this crystal seed.
Yey brighten up the crappy Monday with another video :)
it's so cold outside here on the east coast, I will go buy me some hand warmers today. love this vid Cuz I always wondered about this.
Nice to see Roger again!
I think clicking the metal disc causes the solution to cavitate.
interesting
and thats what i recall too.
A small cavitation thats enough for nucleation to start.
Ben Adams that's why it snaps just like the pistol scrimp aterwise it was single use only
Yeah, if it released particles, those would stay in the water and would inhibite the solution to ever be oversaturated.
This was actually quite a mystery to me as well, and I think I have figured it out. Can't remember which website I read it on, but one of the companies that made this said that the metal disk has a lot of tiny grooves in it that are perforated. When the disk is inverted, the perforated grooves separate slightly; creating this cavity that you mentioned.
I'm definitely going to look out for this item in the stores during this coming winter.
+Nicholas Hylton In summer they are cheaper. Buy and store.
Look how cool Brady looks in the outro.
those video with the thermal image are great !!!!
I bought a hand warmer like that back in the early '90s. Now when I hear about them or see videos about, I think more about the super-saturated solution, and how that relates to cooking, specifically candy making.
I love the thermal camera
Those metal discs don't release anything. They create shock wave (high pressure area) that initiate crystallization. The same effect you have with very cold beer when you slam it hard against the table.
Notice the second heart at 1:28 there are 3 areas where crystallization was initiated.
That metal disc does not release anything. It just creates a shockwave that propagates through the solution. That's enough for nucleation to occur. Remembe that when you have superheated or supercooled water, you also just need to tap the glass to induce state change.
kasuha that what I was thinking as well.
always look forward to seeing these videos
I'm pretty certain the solution is simply a supercooled sodium acetate solution, the little metal disc provides a point of nucleation when bent. Allowing the solution to "freeze" at ~60c (the freezing point of sodium acetate)
I'm not finding a price for that camera on Flir's website, but the site says it's research-grade, and elsewhere I found a similar model number listed at $40,000. The optics are f/1.2 or below (depending on focal length), which is impressive too.
I really love the thermal imaging!
i always was wondering how they're work. I know it's the crystal structure forming. thanksfor the info!
The chemistry, as always, was fun and enlightening. I was even more interested that hand warmers were a thing. Not a big item where I live!
quick question: could you use this chemical system to capture energy from the surroundings, and if so then how efficient would that be ?
Fantastic footage. That camera is amazing.
Brady ... question ... i couldn't help but look at the scale to the right. Seems like the camera footage is interlaced, but the scale isn't ... or vice versa?
very well done video!
thx
Professor Bowley, Great to see you again. Is this new video or are we seeing you via a time machine?
Great video! thanks for sharing!:)
so heartwarming
This videos was... heart warming :D
It's also fun to pour out and make into towers and other things as the super saturated solution crystallizes as it hits the already poured stuff.
Do that with the thermal camera. :)
You looked pretty cool in that outro
I actually did this experiment in lab but never touched the test tube. The way to get sodium acetate crystal is intriguing because acetate is uncommon since acetic acid is weak and won't disassociate easily. Thats why I think sodium hydroxide is used, but in my experiment we used sodium carbonate!
Awesome. never seen one of those, cuz I live next to a desert... but still awesome.
The thin metal disk that triggers the chain reaction actually has tiny fissures throughout it. The disk is stamped out a thin piece of metal and these fissures are created by stamping the metal disk hard enough so that it superficially tears the surface of the metal. Some of the sodium acetate crystals get trapped within these microscopic fissures and pressing or bending that metal disk causes a release or exposure of the crystal(s). It is a supercooled solution.
Since you have rather nice thermal camera it might be nice to show this same effect with the bang a bottle of supercooled water on a desk to make it freeze instantly, that should also warm up as it freezes but not as much.
Sodium Acetate is also the flavoring agent used in salt and vinegar crisps. It is also fairly easy to make at home using distilled vinegar, distilled water and baking soda.
you don't necessarily need the distilled water
Anticonny you might as well use it if your making one of these
Your wedding band is the coolest!
Would hitting the surface quite hard (not hard enough to break it!) work as well to start the nucleation?
I thought this was going to be on the air activated handwarmers. Would be neat to see another video on those.
does the clicker have to release a particle to form a nucleation point? in just thinking about when you hit a bottle of supercooled beer or water and it freezes because of the shock
:O didn't know such things exist, I definitely need to get some of these for ice fishing.
Do you tune those thermal cameras to a certain range?
That's pretty cool!
Professor Bowley!!!!!! I missed him!!
I have a question here.On April 17th 2009 you made a video about erbium and you said its a nuclear poison , can i use it in building constructions in order to protect it from nuclear explosions?
THAT is a PHENOMENAL shirt!
were those veritasium's molecule magnets you were using?
Is sodium acetate solution ever used for cooling systems?
Although liquid metals seem to be used sometimes, nothing has the sheer heat capacity of water, and I'd expect that transfer of heat is much faster if you can use the sodium acetate to keep the temperature gradient high; while absorbing heat from machinery that needs cooling, the solution will keep itself cool for a while rather than quickly reaching near-equalibrium, then when releasing heat out into the environment it can spend much longer being much hotter than the environment using the sodium acetate.
I Love these videos
I've got a question.
I have one of those. It is activated (crystallized). For 8-10 years it layed around in that state.
If I heat it up now, will it be usable?
Try it?
Probably not. My experience is that if one its around in the solid state for even a few months, let alone a few years, enough water is lost that the sodium acetate can never be fully dissolved again. They seem to be more resistant to this loss when in the liquid state, but since they can "fire" accidentally, there is no completely safe way to store them long-term.
+Scott Sakurai
There is no water left in it.
+Harald Sangvik
It didn´t work.
+Scott Sakurai
I have one that stayed there for the same amount of time in liquid form.
Can I activate it and then put it cack in it´s liquid form? Or is it a one time use and I can´t put it back?
If it's still liquid, it is probably still usable no matter how long it has been sitting around. At least I've never had one fail that way, only from sitting in the solid state too long, or the bag tearing.
+Scott Sakurai
The thing is that I remember boiling that thing directly after I used it. It didn´t become liquid again.. Now it stayed there in solid state for 8 years and doesn´t work.
I´ll try the liquid one soon.
I was taught that the crystallisation starts as a result of the shock wave caused by the clicker.
I'm going to have to look into this.
I think the clicker cavitates the water, in other words it creates a low pressure area which would contain water vapour due to the low pressure in the shockwave, and there would be a powder of sodium acetate left behind to catalyze the crystallization.
BooBaddyBig I do think that's a reasonable theory but I did, as promised above, look into this and I have really struggled to find an authoritative answer to this.
The theories seem to be seeding from particles of sodium acetate or iron given off by the clicker (I am highly sceptical of this explanation), your explanation or the shock wave from the clicker pushing atoms into sufficient proximity to form a crystal.
However, look as I might, I cannot find anything more than reasonable opinions and not real research. If anyone knows of any, please tell.
I've always thought it was a shock wave rather than cavitation. The first heat pack I brought said to punch it to activate it and it did not have a metal clicker in it. Also the instant frozen drink trick uses a shock to start the rapid freezing.
I prefer all of the theories here over "a piece of sodium acetate gets clicked off the disk." Especially because the end of the video basically says that couldn't be possible.
How can those degrade over time? I had some of them and after a about a year they never turn quite clear again after boiling them up. They will still activate and produce heat but they somewhat stay crystallized.
This reminds me of an experiment with clear water where you cool it down but it doesnt freez up. Then you drop an impurity or just hit the side of the vessel to create vibration and the water inside freezes .... well ... something along these lines. : )
Greetings professor. Hope you have a great day. Btw im currently studying organic chemistry. What is your experience with that?
it was my understanding that it is the shock wave from the clicker that set of the reaction that crystallizes the solution. am i mistaken?
So is there a chemical reaction that's releasing heat or this crystalization isn't a chemical reaction?
Can you do a video on Flameless Ration Heaters for MREs? Add water, and it heats your food.
Are those Derek's (Veritasium) Snatoms?
*BAD PUN WARNING*
4:45 : Brady, you are so cool there!
This behaves like a super-cool solution. Water will do the same thing. If you are careful you can cool pure water to well below zero degrees. Then if you give the water a slight bump, or there is a tiny particle in the water, the entire container will freeze almost instantly. This process generates heat warming the water to zero degrees.
Is this process the same thing, but with something with a higher freezing temperature?
Wow Derek's snatoms
Expensive though.
MrAntieMatter Haha yeah, loved the jab!
Jason Doe haha yeah, I missed that
sodium tiosulfate disolves at 55c and if not shaken can be chilled down to below room temperature. undercooled sodium tiosulfate acts the same way. temperature raises to its melting point. ref
to supercolled liquid.
There is no such thing as sodium trisulfate.
Lajos Winkler my bad fixed typo its tiosulfate... comonly used as fixative in b/w photography rendering process. the other interesting property dechlorination of water.
Wait I thought it was spring steel and when snapped a nucleation point forms and crystals precipitate proximally. Just like a supercooled water bottle in your freezer if slapped goes from liquid to ice... he made it sound like a chemical catalyst to initiate it's propagation. Anyone Know?
Wait, so I could make one of these at home with vinegar and sodium carbonate?
Yes, you can have a great amount of fun with this stuff.
Yes. Although impurities are a problem with household versions of those chemicals. Nurdrage has a video of trying to make it and dealing with purity issues.
opl500
I knew about the ones that use a rusting reaction to produce heat, but not this one
Hothands and others that use the rust reaction typically last a little longer, but are one time use. These can be boiled to reset.
Since the particle is coming off of the little metal clicker, then wouldn't it have to be sodium acetate? If it was metal, then the particle would remain in the solution when it's boiled and it would spontaneously crystallize again around the existing metal particle.
*So what if* all the water on earth was concentrated with sodium acetate and this reaction would happen on a worldwide scale?
Nice to see Prof. Bowley. o/
Im assuming they just got the thermal camera and theyre having tons of fun with it.
Am I the only one who wants to eat that bag of sodium acetate? i mean, not literally but it just *looks* so delicious
May we have a video on Grignard's reagent next?
One time, the package buried in the microwave(I was trying to revert it) and I didn't think of it, but after awhile, there was a white, powdery residue that smelled very similar to salt and vinegar chips.
That so cool!
Nice!
Anotherbgood one.
Nice rolex! #PeriodicWatches
professor plz be making a video on neutrino...🙂
Why doesn't the piece of metal itself act as a nucleation site? Or, if it does indeed release a tiny piece of metal, why doesn't that metal continue to float around the heart and, after fully reheating and recooling the object, immediately act as a new nucleation site?
Can you please tell a way to memorize the periodic table?
I heart your videos - or is it heat?
Didn't know these were things, sound interesting though.
Where can I buy one of these?
Just google "red heart hand warmer" and a few options show up, even amazon!
Arm123ea Thanks
White Autumn My girlfriend got one from one of those Pure Romance parties, that's the only one I had ever seen until I noticed this video by coincidence. It's about twice the size of the ones in this video but otherwise exactly the same.
+White Autumn in usa, if you live in cold climates, or seasonal climates, you can buy them at nearly any store. even gas stations have hand warmers and feet warmers of all sizes. i just bought some to get ready for winter.
but I've never seen them filled with liquid,'the ones here are all filled with some kind of dry powdered metallic.
maybe it's magnesium?
I'd like to know how the dry hand warmers work - any chemistry guys out there can tell me?