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Solutions
Mixtures
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___________: substances in mixture
are not spread uniformly throughout
mixture.
__________: components uniformly
mixed in solution
The _____the particles the _______the
mix.
Solutions:
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Homogeneous mixture of two or more
substances, the composition of which
may vary within limits.
Consists of two parts:
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_______: (solid, liquid, gas) dissolved substance
or substance present in the smaller amount.
_______: (solid, liquid, gas) substance that the
solute is dissolved in –dissolving medium or
substance present in the larger amount.
Solutes and solvents
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Usually substances are two phases.
Solute changes phase when placed in
solvent.
Examples:
 Aqueous: solvent is________
For example:__________
NaCl in water or ________
______is solute and ______is solvent
Tincture: solvent is ________(C2H5OH)
tincture of iodine
_______is solute and ______ is solvent
Rate of Dissolving
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The quantity solute dissolved per unit of
time.
How fast a solute dissolves
Factors that affect the rate of
dissolving: (think of a sugar cube in coffee)
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_______________
_______________
_______________
Solubility
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Quantity (mass) of solute which can be dissolved in a
given volume of solvent at equilibrium, under
specified conditions of temperature and pressure.
Table ____tells you if something is soluble in water
Table ____ tells you how much at a particular
temperature.
What factors affect the solubility of a substance?
Factors that Affect Solubility
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Nature of solute and solvent:
“Like dissolves like”
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______ and ______ solutes are soluble in
_______solvents. (ex______)
________solutes are soluble in _____ solvents.
Note: Alcohols are soluble in both polar and
nonpolar solvents. Polar and nonpolar solutes are
soluble in alcohol. But ionic solutes are insoluble
in alcohols. Why? ______________________
Factors that Affect Solubility
Temperature:
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For Ionic solids: as T____ solubility ____
example:_____________
For gases: as T _____ solubility ____
example: _________________
Factors that Affect Solubility
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Pressure:
For solids/liquids: as P changes,
solubility______________
For gases: as P____ solubility _______
(____________: escape of gas from solution)
How many types of solutions are there?
Give an example of each type?
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1.
2.
3.
4.
5.
6.
7.
8.
9.
There are ______different types of solutions.
Solid in solid:_________________
Solid in liquid: _______________
Solid in gas: ________________
Liquid in Solid: _______________
Liquid in liquid: ______________
Liquid in gas: _________________
Gas in solid:___________________
Gas in liquid: __________________
Gas in gas: ____________________
There are three common
solutions.
Type 1: Gases in Liquids:
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In a closed system an equilibrium exists between
the gas dissolved in the liquid and the undissolved
gas above the liquid.
The equilibrium is affected by ________
and___________.
An increase in temperature _______the solubility.
An increase in pressure _______the solubility.
(Henry’s law: the mass of a gas which dissolves in a liquid at a
given temperature is proportional to the partial pressure of the gas
over the solution)
Type 2: Liquids in liquids
 There are other liquid solvents besides water.
 Some liquids mix together well while others do not.
1.
________: Liquids that are soluble in one another.
Mix well together. Ex: _____________
2.
________: Liquids that are insoluble in each other.
Do not mix well together. Ex: _________________
Type 3: Solids in liquids
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A solution __________exists when the
opposing processes of dissolving the solute in
the solvent and of crystallizing the solute
from the solvent occur at equal rates.
At this point no further solute can be
dissolved and the solution is known as
______________.
General rule: the solubility of a solid
________as the temperature ________(Table
G)
Looking at solubility
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Solubility curves show the relationship of
grams of solute that may be dissolved in a
solvent at various temperatures.
The solubility curves on Table G in your
reference table show the number of grams of
a substance that can be dissolved in_______
____ at temperatures between 0oC and
100oC.
Each line represents the maximum amount of
a substance that can be dissolved at a given
temperature.
Table G: Solubility Curves
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All of the lines that show an increase in
solubility as temperature increases represent
________being dissolved in water.
Three lines show decreasing solubility with
increasing temperature. These three lines
represent_________and they are:________.
Remember the solubility of all gases
______with increasing temperature.
Concentration
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The concentration of a solution may be
expressed in a variety of ways
Concentrated and dilute: because the terms
are vague they are used for comparison only.
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__________: contains a relatively large amount
of solute.
__________: contains a relatively small amount
of solute
For example: _____________________
Unsaturated, Saturated and
Supersaturated
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1.
2.
3.
When reading the solubility curves on table G you will
need to recognize three positions with respect to the
line of maximum solubility.
When a solution holds less solute than the maximum it can
hold it is said to be___________. In this case the amount
dissolved will be _______the line of solubilty.
When a solution contains the maximum amount of solute that
will dissolve at a specific temperature it is_________. In this
case the amount dissolved will be _________the line of
solubility. Solution____________.
When a solution contains more than the maximum amount of
solute that will dissolve at a specific temperature it
is____________. In this case the amount dissolved will be
________the line of solubility. Made from a saturated solution
at a _______temperature and then ________it. These
solutions are________. One more crystal will cause immediate
___________.
Table G
Recognizing Unsaturated,
Saturated, and Supersaturated
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One method of recognizing the type of solution is if
it contains some undissolved solute, it must be a
saturated solution.
The addition of more solute crystals can also
determine the conditions.
1.
2.
3.
If it dissolves, the original solution was____________.
If it simply falls to the bottom of the container then it
is________________.
If it causes additional crystals to form, the original solution
was_______________.
Concentration of Solution
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The concentration of a solution is a
measurement of the amount of solute
dissolved in solution.
There are several ways of expressing the
specific concentration of solute in a solution.
 Percent by Mass
 Percent by Volume
 Parts per million
 Molarity
 Molality
Percent by Mass &
Percent by Volume
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Percent by mass is simply the mass of the solute divided by
the total mass of the solution, expressed as a percentage
(x100). Use a % sign as the unit.
Percent by mass =
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X
Percent by volume is simply the volume of the solute divided
by the total volume of the solution, expressed as a percentage
(x100). Use a % sign as the unit.
Percent by volume =
X
Parts Per Million
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Parts per million (ppm) is similar to percent by mass because
it compares masses. It represents the ratio between the mass of
a solute and the total mass of a solution. Instead of multiply by
100 you multiply by 1,000,000.
ppm is often used to measure concentrations of solutes that are
present in very small amounts. For example if you wanted to
measure the concentration of chloride ions in tap water.
The units for parts per million are ppm
Parts Per Million =
X
Molarity
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Molarity measures the concentration of a solution in terms of
moles of solute in a given volume of solution.
The Molarity (M) of a solution is the number of _____of solute
in _______ of solution.
When calculating the Molarity of a solution you may need to
make conversions before you solve for and answer.
For example if you are given the mass of the solute you will
need to convert to moles using the mole calculation equation on
Table T.
You may also need to convert the volume of solution given if it
is not in liters.
Molarity (M) =
Molarity by Dilution
Most acids are purchased from laboratory
supply houses in concentrated form.
 If you want to make a different concentration
of acid use the formula below:
________________
Where: M1=initial concentration
V1= initial volume
M2= final concentration
V2= final volume
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Molality
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Molality is the number of ______of
solute per ____ of solvent.
___________
Helpful Hint about Concentration
Problems.
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Remember that a solution is made up of the______ and ______
combined.
So if you are performing a concentration problem you may need
to add the masses or volumes of your “solute” and “solvent” to
solve for the mass or volume of the “solution”, which is what
you need for all concentration equations.
If you are given the mass or volume of the “solution” then you
do not need to worry about adding the solute and the solvent.
Solution =
Colligative Properties
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Properties that depend on the number
of particles rather than the nature of
particles are called____________.
For example:________, _______,
osmotic pressure and vapor pressure.
Non-electrolytes
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Non-electrolytes are molecular
substances that ______break up into
ions (i.e.____________)
_______conduct an electric current
(Why? ______________)
Non-electrolytes have a dissociation
factor (d.f.) of_____.
C12H22O11  C12H22O11 (aq)
1 mole
1 mole
Electrolytes
Electrolytes are ________that ___________when put
in solution.
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For example:________________________________
 Conduct electricity due to___________
 NaCl 
The dissociation factor is equal to_______.
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The more moles of ions produced, the greater the effect on colligative
properties.
Freezing Point Depression
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Freezing point is_______ when a non-volatile
substance (non-electrolyte) is added to a solvent.
When one mole of a nonelectrolyte is added to 1 kg
of water the freezing point is lowered by 1.86
degrees celcius.
For electrolytes the _______particles the ______ the
freezing point.
Example:_________________________
Change in f.p. =____________________
Compare the following:
1 mole of magnesium chloride or 1 mole of sugar in 500g of water
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Which will have the lowest freezing
point?
Which will have the highest freezing
point?
Freezing point will always be lower than 0°C.
Boiling Point ELevation
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Boiling point is _________when a non-volatile
substance (non-electrolyte) is added to a solvent.
When one mole of a nonelectrolyte is added to 1 kg
of water the boiling point goes up by .52 degrees
celcius.
For electrolytes the _______particles the _______
the boiling point.
Example:___________________________
Change in b.p. =____________________
Compare the following:
1 mole of calcium chloride or 1 mole of ethyl alcohol in 500 g of
water.
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Which will have the highest boiling
point?
Which will have the lowest boiling
point?
Boiling point will always be higher than 100°C.