YOU NEED...

• 170g of Sodium Acetate Trihydrate
• Water(tap water is fine)
• Small sauce pan
• Graduated cylinder, 50ml or larger
• Eye dropper
• Glass or 150ml beaker (well cleaned)
• Scale (to measure grams)
• Refrigerator space

PREPARING THE "HOT ICE"...

1) Measure out 30 mL of water (approximately 1 fluid ounce) and pour into a small stove-top pot. Weigh out 170 grams of Sodium Acetate Trihydrate and dump into the pot. Stir the water and sodium acetate trihydrate together to wet the dry flakes.

2) Put the sauce pot over medium heat on a stove and immediately begin to stir the mixture. Keep stirring constantly to avoid burning until the entire mixture turns into a liquid. This may take 10 to 15 minutes.

3) Once the mixture is all liquid with none, or almost none, of the dry sodium acetate still visible, pour the liquid into a clean glass or beaker large enough to hold all of the liquid. Leave any solids behind in the pot if there are any remaining.

4) Put the glass in the refrigerator to cool down. Do not shake or disturb the cooling solution. Check your solution after about five minutes of cooling.

NEXT, EVALUATE YOUR PROGRESS...

1. If you see long thin crystals forming from the sides and bottom of the glass, or a thin layer of white crystals forming on the top of the liquid your ratio of sodium acetate is not quite right yet! (IF THIS IS NOT THE CASE SKIP TO PART C).

2. Take the glass out of your refrigerator and reheat in your pot while stirring to redissolve any solids. Add one to two drops of water. Pour the solution back into your clean glass and return it to the refrigerator to cool. Check again in five minutes and hopefully move on to part C.

3. If you see a clear solution, with or without a thin transparent skin on the surface, your ratio of water to sodium acetate trihydrate is just about perfect. If you have a thin transparent skin on the surface, add a very small amount of water one drop at a time to the glass. Take note of how the skin disappears with just a drop or two of water. Once the skin has disappeared, continue letting the glass cool in the refrigerator.

FINAL PROCESS...

5) Continue checking on your cooling solution every five minutes and make adjustments as necessary according to step four. Wait about 15 to 20 minutes until the outside of the glass feels like it is about room temperature. If there are no signs of any solid material in the glass you are now ready to trigger the hot ice exothermic (release of heat) reaction!

6) Drop a small flake of dry sodium acetate trihydrate into the glass and observe the immediate crystallization that takes place! If nothing happens, or you get a slushy solid,your solution does not contain enough sodium acetate. Add 10g of dry sodium acetate and remix over heat. Start over at step two.

Author - D. Bieniulis for The Science Company, Denver, Colorado