What is hydrogel?
Channel: MEL Chemistry
Date: 2019-11-21

Fun Orbeez balls are just hydrogel! Let’s have a look :)
Equipment: hydrogel granules, water, balloon, plastic bottle, fragrance, glass container, sticker.
Pour the hydrogel granules into a glass container and add water. Over the course of 6-8 hours, the beads absorb the water and swell into transculent balls. If you add flavoring or essential oil to the water, the water beads will act like an air freshener. Fill a plastic bottle with the hydrogel and transfer it into a half-inflated balloon to make an anti stress toy! Place a sticker on the bottom of a glass container and cover it with colorless hydrogel. The image disappears – but if you just add water, the balls become completely invisible and you can see the image again!
Hydrogel is a polymer capable of absorbing and retaining a large amount of water. Most often, it is sodium polyacrylate. Water molecules are relatively small and can soak into the intermolecular spaces of the hydrogel. Hydrogel is also capable of releasing water over time, as the water evaporates from its surface. Hydrogel is widely used in contact lenses, soil hydration, and for various other purposes.
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Safety precautions: perform this experiment only under adult supervision.