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Solutions
Chapter 13
5.0 Chemistry
What is a solution



Solution: A homogeneous mixture of 2 or
more substances in a single physical state.
Suspension: Particles are somewhat
evenly dispersed, but will settle when at
rest. (clay & water)
Colloid: Particle size between suspension
and solution (milk)
Properties of Solutions

Small Particles

Evenly distributed particles

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Particles do not separate when at
rest.
Solubility: The ability to dissolve in
another substance.
Properties of Solutions
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Solute: substance that is dissolved
Solvent: Substance that does the
dissolving
Solvent
Solute
Properties of Solutions


Soluble means something can be
dissolved in something else.
Insoluble means something cannot
be dissolved in something else.
Solid Solutions
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Alloys: Solid solutions that contain
2 or more pure substance.
Advantages of alloys over pure
metals:




Stronger
Cheaper
Resistance from corrosion
Lighter
Alloys
Gaseous Solutions

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The properties of gaseous solutions
depend on the properties of its
components.
Ex. Air
Liquid Solutions

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Miscible Liquids: 2 liquids that can
mix together in any amount
Ex. Alcohol and water
Liquid Solutions
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Immiscible Liquids: 2 liquids that
cannot mix
Ex. Oil and Water
Other types of solutions
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Aqueous Solutions: Solutions with
water as the solvent.
Because water can dissolve so many
things, it is called the universal
solvent.
Electrolyte: A solution that conducts
electricity
Tincture: Solutions with alcohol as
the solvent.
Type of Solution
Specific Solute
IN Specific Solvent
Gas in Gas
Air
O2
N2
CO2
H2O
hydrocarbons
Pt
H2 O
air
lemon juice
water
mercury
silver
carbon
air
sugar
water
carbon
iron
Gas in Liquid
Soda
Gas in Solid
catalytic converter
Liquid in Gas
fog
Liquid in Liquid
Lemonade
Liquid in Solid
teeth fillings
Solid in Gas
smoke
Solid in Liquid
Kool-Aid
Solid in Solid
steel
Concentration and Molarity


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Concentration: Refers to the
amount of solute per given amount
of solvent.
Dilute Solutions – Has little solute
Concentrated Solutions – Has large
amount of solute
Molarity

Molarity – Term used for
concentration
Molarity =
Moles of Solute
Liters of Solution
D. Molarity: (M)
molarity =
moles of solute
liters of solution
M =
n
V
units =
mol
L
Ex #1) What is the molarity of a solution formed by
mixing 10.0 g of sulfuric acid with enough water to
make 100.0 mL of solution?
10.0 g H 2SO4
 1 mol H SO 
2
4

 = 0.102 mol H 2SO4
 98 g H 2SO4 


0.102 mol
M =
 1.02 M
0.1000 L H 2 O
Ex #2) How many grams of bromine are needed to prepare
0.500 L of a 0.0100 M solution of bromine in water?
n
0.0100 M =
n = 0.00500 mol Br2
0.500 L
 160 g Br2 
0.00500 mol Br2 
 = 0.800 g Br2
 1 mol Br 2 
Solubility and the Dissolving Process
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Saturated: A solution is saturated if it
contains as much solute as can possibly
be dissolved under existing conditions of
temperature and pressure.
Unsaturated: Has less than the
maximum amount that can be dissolved.
Supersaturated: Has more than the
maximum amount that can be dissolved.
Saturated vs. Unsaturated
Saturated vs. Unsaturated
Supersaturated
Dilutions

Formula for Dilutions:
M1V1 = M2V2
How a solution forms
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Process of dissolving takes place at the
surface of the solute.
Dissolving Process
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The interaction between the solute and
solvent to allow ions to separate is called
solvation. This interaction is called
hydration when water is the solvent.
Dissolving Process
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
Energy is absorbed when the bonds
break. (endo)
Energy is released when bonds
form. (exo)
Solubility


Solubility is amount of solute that
will dissolve in a specific solution
under given conditions.
See solubility curves
Solubility Graph for NaNO3
180
At 20 oC, a saturated solution
contains how many grams of
NaNO3 in 100 g of water?
90 g
Saturated sol’n
170
160
150
140
oC?
What is the solubility at 70
135 g/100 g water
120
Solubility ( g/100 g water )
What kind of solution is formed
when 90 g NaNO3 is dissolved in
100 g water at 30 oC?
unsaturated
Supersaturated
solution
130
110
100
90
80
70
Unsaturated solution
60
50
40
What kind of solution is formed
when 120 g NaNO3 is dissolved
in 100 g water at 40 oC?
supersaturated
30
20
10
0
0
10
20
30
40
50
60
70
Temperature (deg C)
80
90
100
110
Factors that affect solubility
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1) Nature of Solute and Solvent

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General rule: Like dissolves Like
See example
2) Temperature

As temperature increases, the solubility of
gases and liquids decrease.
Gases are less soluble at high temperatures
than at low temperatures.
Pressure: As pressure increases, the
solubility increases.
Factors Affecting the Rate of Dissolving
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1) Surface Area
2) Stirring
3) Temperature
Altering these 3 factors will either
increase the frequency of collisions
or the energy of collisions between
the solute and solvent.