Forget the old volcano experiment from elementary school. This “hot ice” experiment is much more interesting and uses the same ingredients. All you need is baking soda, vinegar and water.
Add the baking soda and vinegar together. Let them sit for an hour. Then add water. Cook until the mixture is clear, and let it cool down completely. Then, insert a stick or another object and watch the sodium acetate crystals form.
Via Home Science