1. SHHHH! This is Silent reading time!

2. Separating Mixtures and Solutions
Grade 7 Science
Separating Mixtures and Solutions

3. Many products depend on technology for separating mixtures and solutions
What are the three solids and the liquid in the picture below?
White, yellow and brown sugar
Molasses

4. What you will learn: In this chapter, you will
identify separation techniques that are used in and around the home
describe how to use different methods to separate a variety of mixtures
identify examples of how science related to mixtures and solutions affects our lives

5. Student Activity:
Discuss with a partner how you would separate the following mixtures…

6. Separating Mixtures… Mixtures Method of Separation Explanation
Salt Water
Muddy Water
Nuts and Bolts
Iron Filings and Sand

7. Separating Mixtures… Mixtures Method of Separation Explanation
Vegetable Oil and
Sand
Vegetable Oil and Water
Salt and Pepper

8. Discussion Question
“Are the components you have separated still mixtures, or are they pure? Why or why not?”

9. Open your books to page 278

10. Separation Techniques
Mechanical Sorting:
Used to separate the parts of a mixture based on properties such as particle size.
Examples: floatation & magnetism

11. magnetism
floatation

12. Filtration: A common way to separate solid particles from a mixture
The filters can have holes of varying sizes… small to microscopic.

13. Oil filter
Coffee filter
Colander
Furnace filter

14. Evaporation:
Change of state from a liquid to a gas.
Used to recover a solid solute from a solution.

16. Distillation:
Uses two changes of state: evaporation and condensation.
It allows you to recover BOTH the solute and solvent from a solution.

17. Condensation
Evaporation

18. Short Distillation video:

19. Another quick video: http://www.youtube.com/watch?v=Uep3AxaAqLw

20. Paper Chromatography:
Used to separate the colored substances in a mixture such as
ink.
Used to separate the solvents in a mixture.

22. Neat Chromatography activity: http://www. youtube. com/watch

23. Separation Techniques in the Home:
Colanders
Clothes dryers
Window screens
Coffee percolators
Salad spinners
Any others?