1. Types of Mixtures

2. characteristics of these
Mixtures
A combination of two or more substances that do not combine chemically, but remain the same individual substances; can be separated by physical means
Two types:
Heterogeneous
Homogeneous
Based on the prefixes
“hetero” and “homo,”
what do you think are
characteristics of these
two types of mixtures?

3. Heterogeneous Mixture
“Hetero” means different
Consists of visibly different substances or phases (solid, liquid, gas)
A suspension is a special type of heterogeneous mixture of larger particles that eventually settle
Example:
Notice the
visibly
different
substances
Trail Mix

4. Homogeneous Mixture “Homo” means the same
Has the same uniform appearance and composition throughout; maintain one phase (solid, liquid, gas)
Commonly referred to as solutions
Example:
Notice the
uniform
appearance
Salt Water

5. Solution
A mixture of two or more substances that is identical throughout
Can be physically separated
Composed of solutes and solvents
Salt water is considered a solution. How
can it be
physically separated?
the substance in the smallest
amount and the one that dissolves in the solvent
the substance in the larger
amount that dissolves the solute
Iced Tea Mix
(solute)
Water
(solvent)
Iced Tea
(solution)
Colloids (milk, fog, jello) are considered solutions

6. Solutes Change Solvents
The amount of solute in a solution determines how much the physical properties of the solvent are changed
Examples:
Lowering the Freezing Point
Raising the Boiling Point
The freezing point of a liquid solvent
decreases when a solute is dissolved in it.
Ex. Pure water freezes at 320F (00C), but when salt is
dissolved in it, the freezing point is lowered.
This is why people use salt to melt ice.
The boiling point of a solution is higher
than the boiling point of the solvent.
Therefore, a solution can remain a liquid at
a higher temperature than its pure solvent.
Ex. The boiling point of pure water is 2120F (1000C),
but when salt is dissolved in it, the boiling
point is higher. This is why it takes salt water
longer to boil than fresh water.

7. Concentration
The amount of solute dissolved in a solvent at a given temperature
Described as dilute if it has
a low concentration of
solute
Described as saturated if it
has a high concentration of
Described as supersaturated if itcontains more dissolved solute
than normally possible

8. Solubility
The amount of solute that dissolves in a certain amount of a solvent at a given temperature and pressure to produce a saturated solution
Influenced by:
What do we call things that are not soluble?
Temperature
Pressure
Solids increased temperature causes
them to be more soluble and vice versa
Gases increased temperature causes
them to be less soluble and vice versa
Ex. Iced Coffee
Solids increased pressure has no
effect on solubility
Gases increased pressure causes them
to be more soluble and vice versa
Ex. Soda, “The Bends”

9. Review Solutions
Can you see two parts in solutions or are they mixed together so well you only see one thing?
you only see one thing
Are solutions mixtures or pure substances?
Mixtures
What kind of states can a solution be?
Solid, liquid, or gas
What are the two “s” words that every solution must have?
A solute and a solvent

10. In a salt water solution…
Is salt the solute or the solvent?
Solute
Is water the solute or the solvent?
Solvent
What does the solute do?
Gets dissolved
What does the solvent do?
Does the dissolving

11. A Salt Water Solution
Solute (salt)
Animation
Solvent (water)

12. Types of Solutions

13. Solutions What is the Solute and what is the solvent? Label Each.
Cigarette Smoke and Air
Caffeine and Water (Cup of Coffee)
Water and Oxygen (Water in a Fish Tank)
Carbon Dioxide and Sugar Water (Sealed Can of Pop)
Oxygen and Nitrogen (Air)
Minerals and Water (Hard Water)
Water and Sugar (Maple Syrup)
Acetic Acid and Water (Vinegar)
Salt and Water (Ocean Water)
Make your own
solute
solute
solute
solute
solute
solute
solute
solute
Solutions
solvent
solvent
solvent
solvent
solvent
solvent
solvent
solvent

14. Separating Mixtures & Solutions

16. Matter (Solid, Liquid, Gas)
Pure Substances
You can only see one thing because there is only one kind of particle in it.
Mixtures
- can see two parts
Mechanical Mixture
- can see two parts
Solutions
They’re mixed together so well you only see one thing – it looks pure but it isn’t
A solute is the substance to be dissolved (sugar).
The solvent is the one doing the dissolving (water).

17. Suspensions
Suspensions are mixtures with particles large enough to settle out unless the mixture is constantly stirred or agitated.

18. Colloids
Colloids are mixtures with particles intermediate in size between solutions and suspensions.
You cannot see the individual particles.
The particles do not separate upon standing .

19. Examples of Colloids Sol—Solids dispersed in liquids
Example: Paint
Gel—Solid network through a liquid
Example: Gelatin
Liquid Emulsion—Liquids dispersed in liquids
Example: Milk
Foam—Gases dispersed in liquids
Example: Shaving cream
Solid Aerosol—Solids dispersed in gases
Example: Smoke
Liquid Aerosol—Liquids dispersed in gases
Example: Fog
Solid Emulsion—Liquids dispersed in solids
Example: Cheese