1. Solutions, Suspensions, & Colloids
CHAPTER 2
Activity 3
Solutions, Suspensions, & Colloids

2. 2

3. WHAT DO YOU THINK???
One way to get different types of materials is to just mix them together. Lots of different things can happen when materials are mixed. You can get some good food or you can get dynamite. Each kind of mixture has its own characteristics. Taking mixtures apart is a different story.
Is it easier to separate milk from coffee or milk from a bowl of cereal? Why???? 3

4. WHICH ONE IS EASIER? Milk and cereal-
You can use a colander.
Milk and coffee- You would have to boil it (distill it)

5. MATTER
Pure substance
Mixture 5

6. PURE SUBSTANCES VS. MIXTURES
Pure substances contain only one type of particle.
Refer to a, b, and c above.
Mixtures contain more than one type of particle.
Refer to d above.

7. MATTER
Mixture
Pure substance
Homogeneous
Heterogeneous 7

8. Homogeneous or heterogeneous?????
MIXTURES
Homogeneous or heterogeneous????? 8

9. Can be classified as a solution or a colloid
In a HOMOGENEOUS MIXTURE, the different components are not individually visible.
Can be classified as a solution or a colloid 9

10. Referred to as a suspension
In a HETEROGENEOUS MIXTURE, the different components are individually visible and will tend to separate over time.
Referred to as a suspension 10

11. MATTER Mixture Pure substance Homogeneous Heterogeneous suspension
solution
colloid
Silver colloid 11

12. SOLUTIONS Are homogeneous mixtures Contain a solute and a solvent
are transparent (clear)
Air, salt water, metal alloys, are solutions
Light shining through a solution of sodium hydroxide (left) and a colloidal mixture. The size of colloidal particles makes the mixture, which is neither a solution nor a suspension, appear cloudy. (Reproduced by permission of Photo Researchers, Inc.
solute
solvent 12

13. SOLVENT
SOLUTE
SALT
Oxygen
WATER
Nitrogen 13

14. SUGAR GLASS
Sugar glass is a fake glass made from kitchen ingredients. It's used in film stunts because the edges aren't as sharp and dangerous.
It is a solution of water, light corn syrup, sugar and cream of tartar.

15. So how can you tell solutions and colloids
Homogeneous
Solute particles are larger than those in a solution
Most commonly transparent
A liquid-liquid colloid is an emulsion
Difficult to distinguish from a solution with the naked eye.
So how can you tell solutions and colloids
apart?

16. So how can you tell solutions and colloids
THE TYNDALL EFFECT
When a beam of light is shone through a colloid, the larger solute particles scatter the beam of light, enabling you to see the beam as it goes through the mixture.
So how can you tell solutions and colloids
apart?
Solutions don’t scatter light, so you won’t see the beam going through the solution

17. FOG IS A COLLOID

18. COLLOIDS 18

19. COLLOID SOLUTION 19

20. More Less 20

21. EMULSION Is a liquid-liquid colloid.
Milk is a natural emulsion of liquid fat in a watery liquid

22. Emulsion A. Two immiscible liquids, not yet emulsified.
Is a liquid-liquid colloid.
A. Two immiscible liquids,
not yet emulsified.
B. An emulsion of Phase II
dispersed in Phase I.
C. The unstable emulsion
progressively separates. 22

23. SUSPENSIONS Heterogeneous mixture with very large solute particles
Particles can be seen with the naked eye
Particles will settle out in time (OJ, Aerosol Cans)
The particles can be separated with a filter

24. SEPARATING CRUDE OIL Crude oil homogeneous mixture
Separated using a process called fractional distillation
Different substances have different boiling points
ilp.net/labTechniques/FractionalDistillationlAnimation.htm

25. MATTER Mixture Pure substance Heterogeneous Homogeneous suspension
Elements
Compounds
suspension
colloid
solution
solute
solvent
emulsion