Hot Ice





Introduction: Hot Ice

About: I am an undergraduate student pursuing B.Tech in EEE(Electrical and Electronics Engineering).I am passionate about creating new stuffs using technology and hungry to learn more and more.

Sodium acetate or hot ice is an amazing chemical you can prepare yourself from baking soda and vinegar. You can cool a solution of sodium acetate below its melting point and then cause the liquid to crystallize. The crystallization is an exothermic process, so the resulting ice is hot. Solidification occurs so quickly you can form sculptures as you pour the hot ice.

Step 1: Chemicals Reuired

>4 tablespoon Baking soda

>500 ml Vinegar

>2 ml Water

Step 2: Materials Required

>steel vessel

>transparent container


>measuring cup

Step 3: Measure 500ml of Vinegar

I am using a 100 ml measuring cup .

Transfer this vinegar into a vessel.

Step 4: Add Baking Soda to Vinegar

The baking soda and vinegar react to form sodium acetate and carbon dioxide gas.

If you don't add the baking soda slowly, you'll essentially get a baking soda and vinegar volcano, which would overflow your container.

Step 5: Heat the Solution

You've made the sodium acetate, but it is too dilute to be very useful, so you need to remove most of the water.Here is the reaction between the baking soda and vinegar to produce the sodium acetate:

Na+[HCO3]– + CH3–COOH → CH3–COO– Na+ + H2O + CO2

Since the reaction itself produces water as a byproduct there is no need to add water but if the content get thicken add 2 ml water.

Heat the mixture and stir constantly for some time.

Set the soultion to cool down and left unagitted.

Step 6:

Once you remove the sodium acetate solution from heat, immediately cover it to prevent any further evaporation.

Pour the solution into a separate container.

I covered the container with foil paper.

Step 7: Look Out for Results

Remove the solution from the refrigerator after cooling the solution for 30 minutes .

Insert any foreign object which would agitate the solution .

The sodium acetate will crystallize within seconds, working outward from where you agitated the solution .



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Could you clarify the items mentioned in the comments and a bit more? Or maybe edit the text?

What is 00-50 ml? You show a glass of the result. A glass usually gets 250 ml of liquid.

You remove the solution from the refrigerator, but you don't put it there.

We are talking of 500 ml of vinegar. You tell us to add 2 (two) ml of water if the contents get thick. Does it make _any_ difference? Or it is another number that needs editing?

1 reply

Before putting up this instructable I had made 2 attempts to bring out this result so the first thing I noticed was that
Around about 250 ml is left behind after hearing it up

And yes the last picture is of the solution taken out from the refrigerator

Typo errors
Thanks for letting me know

The outcome of this exp was my 3rd attempt so maybe I have commited some errors in my instryctable and I will make sure to correct it

Thank you for the interesting experiment. I have a question:

You say

"Remove the solution once 00-50 ml of the solution is left."

What does that mean? You mean between 0ml and 50ml left?

My solution grew a white crust over the whole surface when there was still 150ml left. Did I do something wrong? I added a bit of water, and am trying now again.

1 reply

Yes you have to remove most of the water
And yes formation of white crust means that you were proceeding correctly

The ingredient list says 2 ml Water... where did you put the water?

2 replies

Do it when you star boiling the contents

If your mixture thickens else the reaction itself produces water as a reactant as you can see it in the chemical equation
Hope that helps you ☺☺

For how long would a sodium acetate "sculpture" last? Is it dependent upon ambient temperature?

This is a cool instructable, hey i have a idea why not do hot ice VS dry ice?

4 replies

yes sure ill work on that very soon

I'd like to make dry ice

Please note that this procedure can be extremely dangerous, with injury potentials due to extreme pressure and extreme cold. Releasing pressurized carbon dioxide gas into atmospheric pressure yields the CO2 into it's solid form.

Get a bottle of industrial CO2 (the kind used for soda pop machines). Secure a nylon stocking over the valve outlet and slowly release the gas into the stocking. Dry ice crystals will begin to form on the stocking. Continue until desired amount of dry ice is captured. Warning! The bottle is at extreme pressure, THREE THOUSAND p.s.i. and the dry ice is 109 degrees BELOW zero.

Dry ice is made with botttled carbon dioxide gas. Search on youtube for videos on how to make dry ice. Its not cheap..

Step 7 says "remove from the refrigerator"

When did you put the solution in the refrigerator?

If you inserted a rod with a couple of RGB LEDs on the end ito the solution, It would be neat to see if that crystal dandelion would glow different colors...

2 replies

Even glow sticks might be neat!

interesting right.

ill try doing this.

Is there a specific purpose, you ask? They used to sell these as hand warmers. They were thick, well sealed plastic pouches, with the sodium acetate solution and a metal "activation disk" inside. You "snapped" the flexible disk to start the hot ice reaction. To recharge, you put the pouches in boiling water, until the ice re-liquefied. What a great teaching aid for showcasing that latent heat is given off by liquids, when they freeze (yes, even water). Great instructable.

1 reply

You can still get those handwarmers fro Lee Valley Tools. I use them while sitting around film sets as an extra and theyre great! About $7.50 CDN$.