1Mixtures-a blend of two or more substances

When we classified matter, we learned that mixtures can be classified as:

Homogeneous (visually the same throughout) or Heterogeneous visually different throughout)

What are some examples of each of these types of mixtures?

2Suspension: a heterogeneous mixture of

2 or more substancesParticles are large enough to settle out and can be separated by filteringi.e. – Muddy water

Colloid3

Colloids: homogeneous mixture of 2 or more substances evenly blended into one another.Substances never

separate (settle out)

4A solution is...Def. - A homogenous mixture of two

or more substancesThe Formation of a solution is a physical change …NOT a chemical

change.Ex. Saltwater, Kool-aid (sugar in H2O)

5

Solute: the substance that is being dissolved •Present in the smallest amount

Solvent: component present in the largest amount (usually H2O).

6Types of Liquid SolutionsAqueousA solution with water as

the solvent ex. Saltwater, Kool-aid

TinctureA solution with alcohol

as the solvent ex. camphor

7Concentrated vs. Dilute

A concentrated solution contains:Large amount of SOLUTE in a

small amount of SOLVENT

A dilute solution contains:Small amount of SOLUTE dissolved in a large amount of SOLVENT

“from concentrate”

SUMMARY

8Solution Concentration Refers to the amount of solute

dissolved in a solvent 5 grams of salt in 100 grams of

waterdiluteVS

35 grams of salt in 100 grams of

waterconcentrated

100 g.

100 g.

5 g

35 g

9

Solid into a Solid-Alloy: two metals dissolved into one another. Ex. steel= iron + carbon

Solid into a Liquid: Salt dissolved in water.Gas into a Liquid: CO2 dissolved (under pressure) into a soda.

10Dissolving the process of creating a solution

through the mixing of solute and solvent particles

Can a solute be dissolved by any solvent? NO!!

11Insoluble When a substance cannot be dissolved in a solvent...

Oil water+ =

The word soluble refers to solutes that CAN be dissolved in a

particular solvent.

12SolubilityA measure of how much solute

can be dissolved in a solvent under certain conditions (i.e. – temp. & pressure)

Example

133 Types of Solubility

Saturated: the maximum amount of solute has been dissolved in the solvent ex. Cup of water w/most salt that will dissolve w/out seeing salt on bottom

Unsaturated: more solute can be dissolved in the solvent ex. Cup of water with one spoon of salt

Supersaturated: more solute has been dissolved than is normally possibleEx. Cup of water w/so much salt in it, salt is on bottom

14Solubility Graphs

Solubility of KCL

0

10

20

30

40

50

60

0 20 40 60 100

Supersaturated

Unsaturated

Saturated

Unsaturated

Supersaturated

15

Any point directly on the line = Saturated

Any point below the line = Unsaturated

Shows the relationship between temperature and solubility

16Dissolving Rate

Def. – The amount of time required for a solvent to dissolve a particular solute

“Speed of dissolving”

17Three Factors Affecting Dissolving Rate of a Solid into a Liquid:

1.Temperature

2. Stirring

3. Surface Area

18Temperature Increasing the temperature

causes an increase in kinetic energy of the solid solute and liquid solvent particles

As the particles move faster, they collide into each other more, thereby increasing the DISSOLVING RATE

19StirringStirring also increases

dissolving rate

Stirring causes an increase in collisions between the particles in a solution

20Surface Area Def. – A measure of how much

exposed area a substance has Breaking, crushing, etc. are ways to

increase the Surface Area Increasing surface area allows more

solute to come into contact with the solvent; increases dissolving rate

VS.

Solubility of Gases 21

Pressure has the greatest effect on the solubility of a

gas in a liquid!

Depends on:1. Pressure = solubility2. Temperature= solubility3. Stirring = solubility