What are Some Special Properties of Solutions?
Chemistry Unit 11: Guided Notes
Main Ideas:
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Mixtures can be either heterogeneous or homogeneous
Concentration can be expressed in terms of percent or in terms of moles
Factors such as temperature, pressure, and polarity affect the formation of solutions
Colligative properties depend on the number of solute particles in a solution
New Skills:
 Calculate concentration in % by mass, % by volume, molarity, molality and mole
fraction
 Calculate gas solubility with Henry’s Law
 Solve solution stoichiometry problems including excess ions.
 Identify soluble and insoluble compounds
Academic Language:
Brownian motion
Colloid
Concentration
Henry’s Law
Immiscible
Insoluble
Miscible
Molality
Molarity
Mole fraction
Saturated solution
Soluble
Solvation
Supersaturated solution
Suspension
Tyndall effect
Unsaturated solution
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Unit 11 Homework:
CALM: http://calm.indiana.edu/
Book: Chapter 14
11.1 Types of Mixtures
 CALM: 5 questions
 p479 #2, 4, 6,7
11.2 Solution Concentration
 CALM: 5 questions
 p481-483 #9,10, 16-18
 p485-487 # 20-22, 24, 25, 27, 29
11.3 Factors Affecting Solvation
 CALM: 5 questions
 p497 #36, 37, 39, 41
11.4 Solution Stoichiometry
 CALM: 5 questions
11.5 Accumulating Content and Skills
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What are Some Special Properties of Solutions?
Chemistry Unit 11: Learning Goals and Objectives
11.1: Types of Mixtures- Nearly all of the gases, liquids, and solids that make up
world are mixtures.
 Compare the properties of suspensions, colloids, and solutions
 Identify types of colloids and types of solutions.
 Describe the electrostatic forces in colloids
11.2: Solution Concentration- Concentration can be expressed in terms of percent or in
terms of moles.
 Describe concentration using different units
 Determine the concentrations of solutions
 Calculate the molarity of a solution.
11.3 Factors affecting Solvation- Factors such as temperature, pressure, and polarity affect
the formation of solutions.
 Describe how intermolecular forces affect solvation.
 Understand what factors affect solubility.
 Define solubility.
11.4 Solution Stoichiometry- Stoichiometry is similar in process as with mass
stoichiometry; concentration calculations are used to start the solution stoichiometry process.
 Solve solution stoichiometry problems and solution limiting reactant problems.
 Determine excess concentration of ions after a reaction.
11.5 Accumulating Content and Skills– Chemistry content is continuous and builds on
prior knowledge and skills. This section will combine this unit with previous units.
 Apply knowledge and skills from previous units to content learned in this unit.
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11.1 Types of Mixtures: Nearly all of the gases, liquids, and solids that make up
world are mixtures.
Objective: Compare the properties of suspensions, colloids, and solutions
Types of Mixtures: There are heterogeneous and homogeneous mixtures:
Heterogeneous - Heterogeneous mixtures are a combination of two or more pure
substances in which each pure substance retains its individual properties. There are two
main types of heterogeneous mixtures:
1. Suspensions – A suspension is a mixture containing particles that settle out if left
undisturbed but, when stirred, the substance will flow like a liquid.

Example:
2. Colloids – A colloid is made of smaller sizes of suspension particles and these
particles do not settle out. Particles cannot be filtered out. The most abundant
substance in a mixture is the dispersion medium.
Example:
•
Objective: Identify types of colloids and types of solutions.
Types of Colloids
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Objective: Describe the electrostatic forces in colloids
Colloids:
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The dispersed particles in a colloid are prevented from settling out because they
often have polar or charged atomic groups on their surfaces. This results in the
formation of electrostatic layers around the particles.
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If you interfere with the electrostatic layering, colloid particles will settle out of the
mixture. Heating also destroys a colloid because it gives colliding particles enough
kinetic energy to overcome the electrostatic forces and settle out.
Brownian Motion
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Brownian motion is the
Tyndall Effect
Concentrated colloids are often cloudy or opaque. Dilute colloids sometimes appear as
clear as solutions. Dilute colloids appear to be homogeneous solutions because their
dispersed particles are so small.
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The Tyndall effect is
Examples:
Homogeneous Mixtures
A heterogeneous mixture is a solution of two or more substances that blend easily and
constant composition throughout. There are different types of homogeneous solutions:
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A solution might exist as a gas, a liquid, or a solid, depending on the state of its
solvent. Water is the most common liquid solvent.
Examples:
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Types of Solutions:
Forming Solutions
Some combinations of substances readily form solutions, and others do not.
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A substance that dissolves in a solvent is said to be soluble in that solvent.
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Example:
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Two liquids
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A substance that does not dissolve in a solvent is said to be insoluble.
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Two liquids
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11.2 Solution Concentration - Concentration can be expressed in terms of percent or
in terms of moles.
Objective: Describe concentration using different units
Expressing Concentration
Concentration can be expressed in terms of percent or in terms of moles.

The concentration of a solution is
Objective: Determine the concentrations of solutions
Practice Problem #1: In order to maintain a sodium chloride (NaCl) concentration
similar to ocean water, an aquarium must contain 3.6g NaCl per 100g of water.
What is the percent by mass of NaCl in the solution?
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Practice Problem #2: 120 ml of Sulfuric acid is mixed with 340 ml of water. What is
the percent by volume of acid in the solution?
Molality
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Molality is the ratio of moles of solute dissolved in 1 kg of solvent.
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Practice Problem #3: In the lab, a student adds 4.5g of sodium chloride (NaCl) to
100.0g of water. Calculate the molality of the solution.
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Mole Fraction
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Mole fraction is the ratio of the number of moles of solute in solution to the total
number of moles of solute and solvent.
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Practice Problem #4: 100 g of a hydrochloric acid solution contains 36 g of HCl and
64 g of H2O. What are the mole fractions of HCl and water?
Objective: Calculate the molarity of a solution.
Molarity
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Molarity is the number of moles of solute dissolved per liter of solution.
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Dilution equation:
Practice Problem #5: A 100.5 ml intravenous (IV) solution contains 5.10 g of glucose
(C6H12O6). What is the molarity of this solution?
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Practice Problem 6: If you needed to make a 1.0 M solution of CaCl2, how many
grams would you need to make 500 ml of it?
Practice Problem #7: Dilution. What volume of 2.00 M calcium chloride stock
solution would you use to make 0.50 L of 0.300 M calcium chloride solution?
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11.3 Factors Affecting Solvation- Factors such as temperature, pressure, and polarity
affect the formation of solutions.
Objective: Describe how intermolecular forces affect solvation.
Solvation
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The process of surrounding solute particles with solvent particles to form a solution
is called solvation.
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Objective: Understand what factors affect solubility.
Factors that Affect Solvation
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Agitation – shaken or stirred – agitation of the mixture allows for more contact
between solute and solvent.
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Surface area –
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Temperature – As temperature increases, the rate of solvation also increases.
Additionally, hotter solvents generally can dissolve more solid solute.
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Objective: Define solubility.
Solubility
Solubility is the ability of a solvent to dissolve a solute.
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In an aqueous solution, a precipitate forms when a mixture produces an insoluble
product.
Solubility Guidelines Reminder
1. All common salts of the group 1 elements and ammonium ions are soluble.
2. All common acetates and nitrates are soluble.
3. All binary compounds of group 17 elements (other than F) with metals are soluble
except those of silver, mercury (I), and lead.
4. All sulfates are soluble except those of barium, strontium, lead, calcium, silver, and
mercury (I).
5. Except for those in Rule 1, carbonates, hydroxides, oxides, sulfides, and phosphates
are insoluble.
Practice Problem #8: Which of the following substances would be a precipitate in an
aqueous solution and why?
a) NaCl
b) CaCO3
c) Fe(NO3)
d) KOH
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Solubility
Unsaturated solutions – An unsaturated solution is one that contains less dissolved solute
than the solvent can handle at a certain temperature and pressure.
In other words, …
Saturated solution – The maximum amount of solute has been dissolved in the solvent. The
amount of crystallization is at equilibrium with the amount of solvation.
In other words,….
A supersaturated solution contains more dissolved solute than a saturated solution at the
same temperature and are considered unstable.
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To make a supersaturated solution, a saturated solution is formed at a high
temperature and then cooled slowly.
The slow cooling allows ……
Solubility of Gases
Gases, in general are less soluble at higher temperatures than at lower temperatures. At
higher temperatures, the gases have a higher kinetic energy that allows them to escape
from a solution.
Henry’s Law
Pressure affects the solubility of gaseous solutes in solutions. The solubility of a gas in any
solvent increases as its external pressure increases.
Carbonated beverages rely on….
Henry’s law states that at a given temperature, the solubility (S) of a gas in a liquid is
directly proportional to the pressure (P) of the gas.
S1 S2
=
P1 P2
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Practice Problem #9:If 0.85 g of a gas at 4.0 atm of pressure dissolves in 1.0 L of
water at 25°C, how much will dissolve in 1.0 L of water at 1.0 atm of pressure and
the same temperature?
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11.4 Solution Stoichiometry - Stoichiometry is similar in process as with mass
stoichiometry; concentration calculations are used to start the solution stoichiometry process.
Objective: Solve solution stoichiometry problems and solution limiting reactant problems.
Stoichiometry applies to solutions too. The number of moles of a reactant and/or product
can be found with concentration using the concentration equations.
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Concentration of ions can be found in a solution by using the ratios in a compound.
For example:
Practice Problem #10: What is the concentration of sodium ions in 1 liter of a 2.0 M
solution of sodium sulfate?
Objective: Determine excess concentration of ions after a reaction.
Practice Problem #11: What mass of solid aluminum hydroxide can be produced
when 50.0ml of 0.200 M Al(NO3)3 is added to 200.0 ml of 0.100 M KOH?
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Practice Problem #12: A 100.0 ml of 0.200 M aqueous potassium hydroxide is mixed
with 100.0 ml of 0.200 M aqueous magnesium nitrate. Write a balanced equation
and net ionic equation. What mass of precipitate is produced and what is the
concentration of each ion remaining in solution after the reaction is complete.
Practice Problem #13: What mass of silver chloride can be prepared by the reaction
of 100.0ml of 0.20 M silver nitrate with 100.0 ml of 0.15 M calcium chloride? Write
the balanced equation and net ionic equation. Calculate the concentration of each
ion remaining in solution after precipitation is complete.
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11.5 Accumulating Content and Skills– Chemistry content is continuous and builds on
prior knowledge and skills. This section will combine this unit with previous units.
Objective: Apply knowledge and skills from previous units to content learned in this unit.

How does the net ionic change the way stoichiometry is calculated? What are the
pros and cons?
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How does concentration affect solutions?
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How is solvation similar to ionic compounds?
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Key Concepts
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The individual substances in a heterogeneous mixture remain distinct.
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Two types of heterogeneous mixtures are suspensions and colloids.
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Brownian motion is the erratic movement of colloid particles.
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Colloids exhibit the Tyndall effect.
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A solution can exist as a gas, a liquid, or a solid, depending on the solvent.
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Solutes in a solution can be gases, liquids, or solids.
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Concentrations can be measured qualitatively and quantitatively.
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Molarity is the number of moles of solute dissolved per liter of solution.
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Molality is the ratio of the number of moles of solute dissolved in 1 kg of solvent.
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The number of moles of solute does not change during a dilution.
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M1V1 = M2V2
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The process of solvation involves solute particles surrounded by solvent
particles.
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Solutions can be unsaturated, saturated, or supersaturated.
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Henry’s law states that at a given temperature, the solubility (S) of a gas in a
liquid is directly proportional to the pressure (P) of the gas above the liquid.
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