In chemistry, there are two important terms, soluble and insoluble. This month, have fun making slimy creations to teach this science concept. If a substance is soluble, it means that it is easily dissolved in another solution. For example, sugar is soluble in water. However, if a substance is insoluble, it does not easily dissolve in another substance. For example, oil is insoluble in water. In some cases, you can have two substances that are soluble in one another, but when mixed makes something new that is not soluble and instead forms a solid. This principle of forming an insoluble product, called a precipitate, is what this experiment explores in a fun and slimy way. Another example is a natural formation of this slimy substance and it is in the aloe plant. The following photo shows a cross-section of an aloe leaf and the slime that is in the middle of the plant, naturally formed. (Pic: Succulent Plants; In Wikipedia. Retrieved May 6, 2013 from: http://en.wikipedia.org/wiki/Aloe
In this activity students will learn how a solid is formed from a liquid mixture.
Liquid white glue
2 Large Sealable Plastic bags
Measuring Cups (1 cup)
Food coloring (optional)
- Fill one plastic bag with 1 cup of water and add one tablespoon of Borax and mix.
- Seal bag and set aside.
- Fill the other plastic bag with ½ cup of water and ½ cup of liquid white glue and mix. Seal and set aside.
- (Optional) Add a few drops of the food coloring to the water/Borax bag and mix well.
- Slowly add the water/glue mixture to the water/Borax mixture.
- Mix the contents together, by gently squeezing the plastic bag.
- Reach in and pull out the slime.
How It Works:
The glue and Borax particles mix together to form a solid that has strong attractions to each other to allow for a new stretchy solid to form. The two liquid solutions were soluble, but when mixed became insoluble. The slime that is made is considered the precipitate. Looking for more, precipitate fun and information, visit: http://bit.ly/103ehLC.
Discussion Questions to Ask:
- What did we add to the mixtures?
- What formed?
- Was the substance formed a liquid or a solid?