When talking about a liquid-what
does the word “solution” mean?
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A homogeneous mixture of two or more
substances in a single physical state
 Liquid
 Solid
 Gas
Solutions are
homogeneous
mixtures
A solute is the dissolved substance in a solution.
Salt in salt water
Sugar in soda drinks
Carbon dioxide in soda drinks
Solvent
A solvent is the dissolving medium in a solution.
Water in salt water
Water in soda
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Solubility can apply to different states of
matter. Ability to dissolve.
Soluble – a substance that is able to dissolve
in another substance.
 Sugar in water
 Salt in water

Insoluble – A substance that does not dissolve
in another substance.
 Oil in water

Solid solutions
 Alloys – two or more metals

Gaseous solutions
 Air

Liquid solutions
 Oxygen in water
 Vinegar (acetic acid in water)

Aqueous solutions
 Ions in water
Nonpolar solutes dissolve best in nonpolar solvents
Fats
Steroids
Waxes
Benzene
Hexane
Toluene
Polar and ionic solutes dissolve best in polar solvents
Inorganic Salts
Sugars
Water
Small alcohols
Acetic acid
Solids tend to dissolve best when:
o Heated
o Stirred
o Ground into small particles
Liquids tend to dissolve best when:
o The solution is cold
o Pressure is high
 A solution that contains the maximum
amount of solute that may be dissolved
under existing conditions is saturated.
 A solution that contains less solute than a
saturated solution under existing
conditions is unsaturated.
 A solution that contains more dissolved
solute than a saturated solution under the
same conditions is supersaturated.
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Do the following in your notebooks:
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15-1 Section Review questions
 #1-4, pg. 505

On pg. 532 do the “Concept Mapping”
activity
What is a solute and what is a
solvent?

The concentration of a solution is the amount
of solute in a given amount of solvent or
solution.
Molarity - the ratio of moles of solute to liters of
solution
Molarity=M= moles of solute
Liters of solution
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You need to be able to calculate molarity
Example:
 What is the molarity of a solution formed by
mixing 10.0g H2SO4 with enough water to make
100.0mL of solution?

To solve:
 Moles of solute?
▪ 10.o g H2SO4
 Liters of solution?
▪ 100.0mL

How do we solve it?
 convert our units
 Divide solute by solution’s total volume
mL L
 Gramsmoles
10.0g H2SO4 x 1mol H2SO4
0.100 L solution
98.1 g H2SO4
 Answer 1.02 M
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Practice #1
Vinegar is a solution of acetic acid. What is
the molarity of the solution when 125 g of
acetic acid (C2H4O2) is dissolved in enough
water to make 1.50 L of solution?
Answer
 1.39M
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Practice #2
How many grams of bromine are needed to
prepare 0.500 L of a 0.0100 M solution of
bromine in water?
Answer
 0.799 g
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To learn more about molarity and how to
calculate it we will be doing a lab!
Beer’s Law (named after a person, not a
beverage) states that you can determine the
concentration of a solution by how much
light it absorbs.
So, you will be making solutions of different
concentrations and testing them

Important to remember
 Your measurements and calculations must be
exact!
 If you do not measure right, you will ruin your
solution and you will have to begin again
 You will do a graph-this MUST be done on graph
paper or by computer-NO exceptions
Mole fraction – the ratio of moles of solute to
total moles of solution
nA
Mole fraction of A   A 
n A  nB
Calculate the Molarity of 98 grams of
sodium hydroxide in 2.2 liters of
solution.
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Getting started:
Create a data table
Make up your solution
 This is from the calculations you made yesterday
 50 mL total
 You will use this to create all the dilutions

T0 make your dilutions:
 M1V1=M2V2
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After you create the dilutions you will place a
sample of your solution in the colorimeter
You will graph your results-on graph paper