Subject Area: Science
Objective: Mixtures and solutions can be separated through the use of filters or evaporation.
Materials: Sand, water, salt, clear glass saucers and glasses, coffee filter
Procedure:
1. The students will mix sand with water (A mixture).
2. The students will write down their observations.(The sand will change color and settle near the bottom.)
3. The students will mix salt with water (A solution).
4. The students will write down their observations. (The salt will dissolve in the water.)
5. The students will use the coffee filter to strain the sand from the water.
6. The students will write down their observations. (The sand will remain in the coffee filter, separate from the water.)
7. The students will use the coffee filter to strain the salt from the water.
8. The students will write down their observations.(The salt remains dissolved in the water.)
9. The students will place the jar of saltwater out to evaporate. (This may take several days depending on the amount of water in the jar. Or, the students can boil the saltwater until the water has evaporated; leaving the salt behind.)
10. The students will write down their observations. (The salt is left behind.)
Justification:
The students will clearly observe how scientists use filters and evaporation to separate the elements in mixtures and solutions. They will also observe how the elements do not change. Each element retains its own characteristics and properties. This lesson expands Lesson Plan #1 by using a realistic lab experiment for the mixture and utilizing solutions, filters, and evaporation. The students can take what they learned about mixtures with the lesson with the fruit and apply this knowledge to Lesson #2. Then, the knowledge is expanded through the introduction of solutions and the use of filters and evaporation as a means to separate elements from each other.
