SOLUTIONS

RECALL

TYPES OF MIXTURES:

SUSPENSIONSCOLLOIDS

SOLUTIONS

All mixtures are physically combined and can be physically separated.

DEFINITION

A solution is a homogeneous mixture of two or more substance in a single physical state

Parts of a solution

SOLUTE – the substance that is dissolvedSOLVENT- the substance that does the dissolving

Definitions

Solute Solute - KMnO4 Solvent Solvent - H2O

TYPES OF SOLUTIONS

SOLUTE SOLVENT EXAMPLEGAS GAS AirGAS LIQUID Seltzer (CO2)

LIQUID LIQUID Antifreeze (ethyl glycol in water)SOLID LIQUID Sea water ( salt in water)GAS SOLID Charcoal filter (poisonous gases in

carbon)LIQUID SOLID Dental filling (mercury in silver)SOLID SOLID Sterling silver (copper in silver)

SOLID SOLUTION

• Contain two or more metals called alloys• Formed by melting the components and

mixing them together and allowing them to cool

• Properties of alloys are different from the original component metals

TYPES OF ALLOYSALLOY COMPONENT USES

Babbitt Tin, antimony, copper Bearings

Bell metal Copper, tin Bells

Coinage metals Copper, tin, zinc Coins

16 karat gold Gold, copper, silver Jewelry

Sterling Silver, copper Jewelry, flatware

Nichrome Nickel, iron, chromium, manganese

Heating elements

GASEOUS SOLUTIONS

• All mixture of gases• Properties depend on the properties of its

componentsExample: Nitrogen in air serves as a gas that

dilutes pure oxygen which is toxic to people and animals, and is very combustible.

LIQUID SOLUTIONS• Most familiar type of solution• The solvent and the solution are liquids• Solute may be a gas, a solid, or a liquid• It is proper to describe liquids that are soluble

to each other as MISCIBLE or can mix. And insoluble liquids as IMMISCIBLE. Or cannot mix. Example: alcohol is miscible in water while oil is immiscible in water.

Important terminologies:

• Soluble – substance that dissolves another substance

• Insoluble – substance that does not dissolve another substance

• Miscible – liquids that are completely soluble in each other or can mix

• Immiscible – liquids that are not soluble in each other or cannot mix

AQUEOUS SOLUTIONS

• Solutions with water as the solvent• Aqueus, means like or containing water.• Substances that dissolve in water are

classified according to whether they produce ions or molecules in solution.

• Solutions that conduct electricity are called ELECTROLYTES.

SOLUBILITY

SolubilitySolubilitySolubility

maximum grams of solute that will dissolve in 100 g of solvent at a given temperatureg solute/100 mL H2O

varies with temp

based on a saturated solution

Solubility

SATURATED SOLUTION

no more solute dissolves

UNSATURATED SOLUTIONmore solute

dissolves

SUPERSATURATED SOLUTION

becomes unstable, crystals form

increasing concentration increasing concentration

Determine if a solution is saturated,unsaturated,or supersaturated.

• If the solubility for a given substance places it anywhere on it's solubility curve it is saturated.• If it lies above the solubility curve, then it's supersaturated,• If it lies below the solubility curve it's an unsaturated solution.

Temp. (oC)

Solubility(g/100 g H2O)

KNO3 (s)

KCl (s)

HCl (g)

SOLUBILITYCURVE

Solubility how much solute dissolves in a given amt.

of solvent at a given temp.

unsaturated: solution could hold more solute; belowbelow line

saturated: solution has “just right” amt. of solute; onon line

supersaturated: solution has “too much” solute dissolved in it;

above the line

To

Sol.

To

Sol.

Solids dissolved in liquids Gases dissolved in liquids

As To , solubility As To , solubility

Sometimes you'll need to determine how much additional solute needs to be added to a unsaturated solution in order to make it saturated.

For example,30 grams of potassium nitrate has been added to 100 cm3 of water at a temperature of 50ºC.

How many additional grams of solute must be added in order to make it saturated?

From the graph you can see that the solubility for potassium nitrate at 50ºC is 84 grams

If there are already 30 grams of solute in the solution, all you need to get to 84 grams is 54 more grams ( 84g-30g )

Solubility Table

LeMay Jr, Beall, Robblee, Brower, Chemistry Connections to Our Changing World , 1996, page 517

shows the dependence

of solubility on temperature

0 10 20 30 40 50 60 70 80 90 100

Solubility vs. Temperature for Solids

Sol

ubili

ty (

gram

s of

sol

ute/

100

g H

2O)

KI

KCl

20

10

30

40

50

60

70

80

90

110

120

130

140

100

NaNO3

KNO3

HCl NH4Cl

NH3

NaCl KClO3

SO2

gases

solids

Classify as unsaturated, saturated, or supersaturated.Classify as unsaturated, saturated, or supersaturated.

per100

gH2

O

80 g NaNO3 @ 30oC

45 g KCl @ 60oC

50 g NH3 @ 10oC

70 g NH4Cl @ 70oC

=unsaturated

=saturated

=unsaturated

=supersaturated

0 10 20 30 40 50 60 70 80 90 100

Solubility vs. Temperature for Solids

Sol

ubili

ty (

gram

s of

sol

ute/

100

g H

2O)

KI

KCl

20

10

30

40

50

60

70

80

90

110

120

130

140

100

NaNO3

KNO3

HCl NH4Cl

NH3

NaCl KClO3

SO2

gases

solids