How to make an apple levitate?

This is an interesting experiment. Let me tell you, it actually just requires some common chemical materials from the kitchen to get started, and it's very simple. First, prepare the following items: 1. One spoon of salt 2. One to one and a half spoons of alum 3. Three spoons of beer yeast 4. Half a cup of high fructose syrup 5. Three cups of water. Then, two hours before the experiment, mix these materials in a large cup and put it in the refrigerator. During the experiment, place the large cup on the stove to heat it up. When it looks like it's about to boil, carefully put the apple into the cup, and then just wait for the fun results. Here's a video explaining the principle...