Dude! That is so cool! I’d love to do that at home with my kids.

Why is it freezing in the metal pan, but, not the plastic one …until you touch it, that is? The kids would love the plastic one, so they could touch it and cause it to freeze.

Very cool
I’m going to give it a try too

I think they had touched the pans first to get some of the oil’s on it, that’s why it started to turn as they poured.

It’s the same principle that is used to create rock candy- the sodium acetate has a much lower melting point than you’d expect (around 60 C), so when it is heated in the water, the solid you see turns to a liquid that ‘blends’ into the water.

On top of this, at a high temperature water can hold much more solute than at lower temperatures, but when you lower the temperature, that solute doesn’t just precipitate out right away, you get a supersaturated solution.

By touching it, he provided a nucleus for solid crystals to start forming, then after that it was just a self-sustaining reaction. I suspect that it froze on the metal pan and not when it was poured into the plastic because:

1. it was being poured from a greater height, disturbing the solution more
2. metal is probably a better nucleus for solidification than plastic.

If I got this wrong, chemists, please feel free to beat me with a large stick

Wow that IS cool!

Cool, it looks a bit like wax. I’ve always wondered what those multi-use bags contain that warm up when you bend them, now I know

Wow, that was totally awesome!! You sure conger up some cool stuff!!! I mean stories!

Coolio!!!!!!!!!!! Im a 5th grader and thats what i’m gonna do for my science project so i guess ill give it a shot

Chemistry teacher here. I’ve done this demo in class for more years than I care to remember.

Chris R.’s explanation above is absolutely correct. Good on ya’ for paying attention in class! Sodium acetate supersaturates very easily because the acetate ion has a very “diffuse” charge when dissolved in water (it doesn’t have one particular “sticky” spot to strongly attract the positive sodium ion.)

You can make rock candy (large sugar crystals) the same way (but it doesn’t crystallize as quickly.) Dissolve as much sugar as possible in boiling water then let it cool slowly in a **clean glass** container. Then dangle a string in to provide a nucleation site.

Yea Sodium acetate Hot Ice is great you can buy it from ebay

Sooo…. this is really cool but make sure you do it right or it won’t work….. my friend tried doing it and it didn’t work because she didn’t sterre it all the time

HAVE FUN! TRY IT!

im in the 8th grade and i am doing this experiment for my science fair proj. Is there anything specific with like the water or anything? Can it just come from the sink or does it need to be soemhting different? and how long would i need to put it in the fridge to cool?

You need distilled water and im doin it as a 5th grade science project

Chemistry Teacher here again.

Distilled or deionized water would be best but you can do it with any filtered or bottled water. The main idea is that there can’t be any “junk” floating around that could start the crystallization process before you want it to happen. Clean, well-scrubbed glassware is also a must for the same reason. Make a bunch of small samples because one or two may crystallize on their own no matter what.

I start by filling a few small test tubes with the NaH3CCHO then adding just a few drops of water to each (that’s all it takes). Heat them up in a hot water bath and stir each with a glass rod. When entirely dissolved, take them out and let cool to room temperature (NO FRIDGE NECESSARY!)

As long as no dirt gets in you can use the same samples over and over. Just reheat. Good Luck.

Whoops, that should have been NaH3CCO2. What was I thinking?

I also forgot to mention, sodium acetate is a hydrate (which means that the crystals already contain a fair amount of water). This is why you don’t need to add much water to get it to dissolve.

You can also make your own NaCH3COO (get used to different nomenclature!) It is the result of the well-known “kitchen” reaction of baking soda (sodium bicarbonate, NaHCO3) with vinegar (acetic acid, CH3COOH). You have to use distilled vinegar–no balsamic here! Use excess baking soda to react all the vinegar, filter out the unreacted baking soda, then boil the solution to drive off as much water as possible. Remember, you won’t see the crystals until it cools.

thanks, yall just helped me A LOT. I just havnt really been able to find specific directions to do this experiment.

omg i have a project due with a partner and she wanted to this.. i couldnt find any info just videos the comments helped alot thnxx

This is not ice, it is sodium acetate turning solid…I wouldn’t put it in my drinks x_x

I just fould out about this and it looks fun, but i can t find any sodium acetate. can some one tell me were too look other than Ebay.

when freezing it does it have to be at a sorten Temp befor i take it out??

Before you ask any more questions why don’t you read all the posts? I’ll bet your question has already been answered.

Temperature: It will work at room temperature or lower (but as it gets colder there’s a greater chance that it will spontaneously crystallize.)

Suppliers: As has been mentioned by previous posters you can find sodium acetate already pre-mixed in the right proportion with water (very little water, actually) as heat packs. It took about 5 seconds on Google to find these online suppliers (I Googled “heat pack”):

http://www.amazon.com/Instant-Reusable-Pack-Heating-Packs/dp/B000F3Q524
http://www.9thtee.com/reheater.htm

I’m trying to reason out how snapping the metal disc starts the crystallization. My current theory is that the shockwave aligns the acetate ions which starts the ball rolling. (Non-spherical particles suspended in a fluid will align during any shearing flow. This is sickeningly close to work I did for my Master’s thesis. Don’t ask.) Anyone else have any ideas?

Oops. Double post.

And read ALL the comments before you ask a question that has already been answered!

Hi there: HOT ICE …………..

My daughter and I just got the sodium acetate today. We put some in near boiling water and stired alot. Put it in fridge to cool - tried it - it did’nt work.

Did it a second time - its in the fridge now.

Her science fair is due in 3 days! I only bought 500 grams and its going fast!!!

Please e-mail me if you have made it successfully - with exact instructions please help.

Running out of time and sodium acetate!

Thanks

Most likly you didn’t use enough sodium acetate in the water

JEFF
Thanks for your advice, you have been the only person I have found (and I searched everywhere) who could explain how to do this. Thanks again

Oh and you lot really should read all the posts by Jeff if you want to know how to do it properly

Jeff–what chemical principles are demonstrated in this experiment? crystallization? nucleation? help??