A couple of my friends and I made hot ice for our school science fair. We used sodium acetate. This project won first place at my schools science fair!!!
A glass cup
and Sodium acetate (you can find it online or in certain heat packs)
How to do it:
You heat water in a pot and put the sodium acetate in the water. You will want to dissolve as much sodium acetate into the water as you can. Bring the water to a simmer but don't boil. Once it is fully dissolved pour it into a glass cup and put it in the refrigerator. Take it out of the refrigerator when it gets to room temperature. Put a little bit of undissolved sodium acetate on your finger and touch the liquid. It will crystallize and become hot!!
It is really fun and you should do it! Tell your friends about this video and don't forget to comment!