The water baby pinching tutorial is as follows:

Experimental materials:

Sodium alginate, calcium lactate, measuring cup, pigment, hemispheric mold, stirring rod, hot water , clear water.

Experimental steps:

1. Pour about 10g of sodium alginate into the measuring cup, add 240ml of hot water, drop in the pigment, stir for 10 minutes, let it sit for 5 minutes and continue stirring for 5 minutes. Minutes, add the pigment and let it sit for about an hour, we can get a thick sodium alginate solution.

2. Pour about 450ml of water into a measuring cup, add 25g of calcium lactate, and stir with a stirring rod until there are no particles to obtain a clear calcium lactate solution.

3. Take the hemispherical mold and soak it in the calcium lactate solution. Slowly pour a little sodium alginate solution into the mold. Then slowly immerse the mold in the calcium lactate solution. Shake the mold gently and put it in place. Turn the grinding tool over and the water elf ball will separate from the mold. Different colors of pigments can make more colorful water elves.

4. After soaking the water elf in the calcium lactate solution for 5 minutes, you can take it out and put it into clean water. The longer it is soaked, the better its elasticity will be.

Experimental principle:

One of the materials used in the experiment is a substance called "sodium alginate". After heating water, it will quickly form a gel, and then add calcium lactate. When soaked in water, the calcium ions in the calcium lactate solution will quickly undergo ion exchange, thus forming a gel film on the surface, and the "water elf" will slowly solidify.

The true identity of the water baby sold outside is a kind of water-absorbent resin, which is usually made of starch mixed with acrylonitrile or acrylate. Both acrylonitrile and acrylate have certain toxicity, and the merchants are It is also impossible to use expensive food coloring in the production, and some industrial coloring may be added. Therefore, it is recommended that children should not play with this kind of thing. If it comes into contact with the skin, they should wash it immediately. Children should not eat it by mistake, otherwise the consequences will be disastrous, so parents should also be very careful.