Chapter 16 Notes
Honors Chemistry
Chapter 15 and 16: Water Solutions
Section 1 Notes – Properties of Solutions
(Read pages 471-477)
Solvation
 The ______________________ by which the ______________________ and ______________________
ions of an ______________________ solid become surrounded by ______________________
______________________
Terms to Know
 ______________________
o The ______________________ medium
 Solute
o The ______________________ that is ______________________
 Example: ______________________
o Solute = ______________________
o Solvent = ______________________
The Solution Process
Factors that affect solution formation
 ______________________ of ______________________ and ______________________
 ______________________ (Agitation)
 ______________________ of solution
 ______________________ ______________________ of dissolving particles
Stirring and Solution Formation
 ______________________ speeds up how fast the ______________________ dissolves because it
allows more contact between ______________________ and ______________________ particles
 Note: Stirring speeds up how fast the solute dissolves, not ______________________
______________________ solute is dissolved
Temperature and Solution Formation
 ______________________ temperature ______________________ how fast the solute dissolves
 Increasing ______________________ increases the ______________________
______________________ of the solvent particles
 The solvent particles collide ______________________ often and ______________________ rapidly
with solute particles
Surface Area and Solution Formation
 More surface area, or more ______________________, means there is a ______________________
likelihood of ______________________ between ______________________ and
______________________ particles
 This ______________________ how fast the solute dissolves
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Chapter 16 Notes
Honors Chemistry
Solubility
 Solubility – the amount of ______________________ that ______________________ in a given quantity
of ______________________ at a constant ______________________ and ______________________
o Unit: ______________________ of ______________________ per 100 g of
______________________
So why doesn’t all the solid just dissolve?
 ______________________ involves an ______________________ process
o ______________________ - dissolving
o ______________________ - solidifying
 Particles ______________________ solution at the same time as particles ______________________
solution
 The solution can only “contain” a certain number of ____________________ at a ___________________
Different Types of Solutions
 ______________________ Solution
o Contains ______________________ than the maximum amount of solute that can be dissolved
o ______________________ solid residue present
 ______________________ Solution
o Contains the ______________________ amount of solute that can be dissolves
o ______________________ or ______________________ not have solid
______________________ present, depending on how much solute is added
 ______________________ Solution
o Contains ______________________ than the maximum amount of solute that can be dissolved
o Made by ______________________ ______________________ and ______________________
o ______________________ will occur as temperature or pressure ______________________
Miscible vs. Immiscible (Liquids)
 Miscible
o Two liquids that ______________________ in each other in all ______________________
 Immiscible
o Two liquids that are ______________________ in one another
 Example:
 __________________________________
Solubility Charts
 How to read a solubility chart:
o The ______________________ shows the number of grams in a ______________________
solution containing 100 mL or 100 g of water at a certain ______________________
o Any amount of solute ______________________ the line indicates the solution is
______________________ at a certain temperature
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Chapter 16 Notes
o
Honors Chemistry
If the amount of solute is ______________________ the solubility curve, the could indicate two
things:
 The solution is ______________________ if the correct ______________________ and
______________________ conditions are present
 The solution is ______________________ with ______________________ solute on the
bottom
More about values above the curve:
 If the amount of solute is ______________________ the line but has not all dissolves, the solution is
______________________ and the number of grams of solute settled on the bottom of the container
equals the ______________________ number of grams in solution minus the number of grams in a
______________________ solution at that temperature (according to the ______________________)
 Grams of solute on bottom = # grams in ______________________ - # grams in
______________________ solution
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Chapter 16 Notes
Honors Chemistry
Use the solubility curve in your notes to answer the following questions:
1. What are the customary units of solubility on solubility curve?
2. What is the solubility of ammonium chloride at 60˚C?
3. At what temperature do potassium chlorate and potassium chloride have the same solubility in water?
4. A saturated solution of which compound contains 130 grams of solute per 100 grams of water at 70˚C?
5. Are the following solutions unsaturated, saturated, or supersaturated?
a. 80 g of sodium nitrate in 100 g of water at 30˚C __________________________________
b. 80 g of potassium chlorate in 100 g of water at 50˚C __________________________________
c. 70 g of ammonia in 100 g of water at 10°C__________________________________
6. Which of the salts shown on the graph is the least soluble in water at 10˚C?
7. At what temperature do saturated solutions of potassium nitrate and sodium nitrate contain the same
weight of solute per 100 mL of water?
8. What is the lowest temperature at which 30 grams of potassium chloride can be dissolved in 100 mL of
water?
9. How much undissolved solute is in a 10°C of NaNO3 containing 110 g of solute?
Factors Affecting Solubility
 ______________________
 ______________________ (______________________ only)
 ______________________
Temperature Effects on Solid Solubility
 ______________________ temperature ______________________ the rate at which a solid dissolves
o ______________________ temperature means that the particles in solution move
______________________ and collide more ______________________ and more
______________________ with the solute particles
 Cannot predict whether it will ______________________ the amount of solid that dissolves
 Must read it from a ______________________ or ______________________ data
Temperature Effects on Gas Solubility
 As temperature ______________________, gas solubility ______________________ because the gas
molecules can move fast enough to escape
 This is why a soda bottle becomes more ______________________ as it warms up (more “whoosh”
when you open the bottle)
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Chapter 16 Notes
Honors Chemistry
Pressure Effects on Gas Solubility
 Pressure has little solubility effect on ______________________ and ______________________ because
they are ______________________
 For gases, an ______________________ in pressure causes an ______________________ in solubility
 This explains why the “fizziness” of soda is lost after you break the seal of the bottle
Henry’s Law
 States that at a given ______________________, the ______________________ of a gas (S) in a
______________________ is ______________________ proportional to the pressure of the gas
______________________ the liquid (P)
 Equation:
Henry’s Law Practice Problems
1. If the solubility of a gas in water is 0.77 g/L at 3.5 atm, what is its solubility of the gas at 1.0 atm of
pressure? The temperature is held constant.
2. The solubility of a gas in water is 0.16 g/L at 104 kPa. What is the solubility when the pressure is
increased to 288 kPa at constant temperature?
3. A gas has a solubility in water at 0°C and 1 atm of 3.6 g/L. What pressure is needed to produce an
aqueous solution containing 9.5 g/L at 0°C?
Structure Effects on Solubility



Looking at the structure of the ______________________ and ______________________ (in terms of
______________________)
Solute-Solvent Interactions
Solubility Rule: __________________________________________________
Book Work – Page 477 #3-7
Section 2 Notes – Concentrations of Solutions
(Read pages 480-486)
What is concentration?
 A ______________________ of the amount of ______________________ that is dissolved in a given
quantity of ______________________
 Two classifications
o ______________________________: A small amount of solute dissolved
o ______________________________: A large amount of solute dissolved
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Chapter 16 Notes
Honors Chemistry
Molarity
 Unit of ______________________
 Molarity = ________________ of _________________/__________________ of _________________
 Unit: _________________ (Molar)
o Example: 6 M HCl is ___________________________________________________
Reminder: How to calculate moles from grams
 ______________________________________________________________________________
Molarity Calculation
Intravenous (IV) saline solutions are often administered to patients in the hospital. One saline solution contains
0.90 g NaCl in exactly 100 mL of solution. What is the molarity of the solution?
Molarity Practice Problems
1. A solution has a volume of 2.0 L and contains 36.0 g of glucose. The molar mass of glucose is 180
g/mol. What is the molarity of the solution?
2. A solution has a volume of 250 mL and contains 0.70 mol of NaCl. What is the molarity of the solution?
3. A 2 L solution of LiBr has a molarity of 1.2 M. How many moles of solute does this solution contain?
4. How much solvent (L) must be added to 3.6 mol of KCl to make a 5 M solution?
Making Dilutions
 Diluting a solution ______________________ the number of moles of ______________________ per
unit ______________________, but the total number of moles of ______________________ in solution
does not change
 This can be useful for scaling down stock solutions
 Equation:
o
o
o
o
M = ______________________
V = ______________________ (units can be L or mL, must be the same on both sides)
1 = ______________________
2 = ______________________
Dilution Sample Problem
How many milliliters of aqueous 2.00 M magnesium sulfate solution must be diluted with water to prepare 100.0
mL of 0.400 M magnesium sulfate solution?
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Chapter 16 Notes
Honors Chemistry
Dilution Practice Problems
1. How many milliliters of a solution of 4.00 M KI are needed to prepare 250.0 mL of 0.760 M KI?
2. How could you prepare 250 mL of 0.20 M NaCl using a solution of 1.0 M NaCl and water?
Percent Solutions
 Remember percent composition from Chapter 10?
 Percent Solution can be calculated in 2 ways:
o Percent by ______________________ (%v/v)
o Percent by ______________________ (%m/m)
Percent by Volume
 Equation
Percent Volume Sample Problem
What is the percent by volume of ethanol when 85 mL of ethanol are diluted to a volume of 250 mL?
Percent by Mass

Equation
Percent Mass Sample Problems
1. Suppose you make a 250 g solution of glucose with 100 g of glucose, what is the percent by mass
glucose?
2. Suppose you want to make 2000 g of glucose solution with a (%m/m) of 2.8%, how much glucose do you
need?
Book Work – Page 486 #16-23
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Chapter 16 Notes
Honors Chemistry
Section 3 and 4 Notes – Colligative Properties of Solutions and Colligative Calculations
(Read pages 487-496)
Molality
 Be careful, its molaLity not molaRity!
 Another way to express solution ______________________
 Molality =



Unit is m, called ______________________
Conversion from grams to kilograms  __________________________________
Conversion from grams to moles  __________________________________
Molality Sample Calculation
1. Calculate the molality of a solution prepared by dissolving 10.0 g of NaCl in 600 g of water.
2. How many moles of potassium iodide must be dissolved in 500.0 g of water to produce a 0.060 m KI
solution?
3. How many grams of sodium fluoride are needed to prepare a 0.0420 m NaF solution that contains 750 g
of water?
Mole Fraction
 Also used to express ______________________
 Relates the ______________________ of ______________________ or ______________________ of
______________________ to ______________________ moles in solution
 Represented by ______________________
 No units!!
 Two formulas:
o
n represents number of ______________________
Mole Fraction Sample Problem
Ethylene glycol is added to automobile cooling systems to protect against cold weather. What is the mole fraction
of each component in a solution containing 1.25 mol of ethylene glycol dissolved in 4.00 mol of water?
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Chapter 16 Notes
Honors Chemistry
Mole Fraction Practice Problem
A solution contains 50.0 g of carbon tetrachloride dissolved in 50.0 g of chloroform (CHCl3). Calculate the mole
fraction of each component in the solution.
Colligative Properties


A property that depends on upon the ______________________ of ______________________ particles,
not their ______________________
Three Types:
o ______________________ ______________________ Lowering
o ______________________ ______________________ Elevation
o ______________________ ______________________ Depression
Vapor Pressure Lowering





Vapor Pressure: The pressure exerted by a vapor that is in ______________________ with its liquid in a
closed system (entering and exiting solution the same ______________________)
In a ______________________ solvent, the solvent particles simply have to overcome the
______________________ forces between solvent molecules in order to ______________________,
therefore vapor pressure is ______________________ (easy to vaporize)
o Measured in terms of ______________________ - or ability to vaporize
Adding a __________________ solute (such as ______________________ or _____________________)
______________________ the vapor pressure of a solution by ______________________ the attractive
forces that solvent particles must overcome
SUMMARY: The ______________________ particles you have, the ______________________ the
vapor pressure!
Think about it…
Which solution would have the lowest vapor pressure?
1.
2.
3.
4.
Pure water
Water with dissolved calcium chloride
Water with dissolved sodium chloride
Water with dissolved glucose
Boiling Point Elevation





Similar to the concept of vapor pressure lowering
A substance boils when the particles in solution gain enough ______________________ to overcome the
______________________ forces of the liquid and can escape into the ______________________ phase
In a pure solvent, the particles must only overcome the attractive forces from other
______________________ particles
When a ______________________ solute is added to the solution, the solvent particles must overcome
the attractive forces of both the ______________________ and ______________________
When ______________________ particles are added to a solution, the boiling point
______________________
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Chapter 16 Notes
Honors Chemistry
Boiling Point Elevation Calculations
Equation:



ΔT = __________________________________
Kb = __________________________________
msolute = __________________________________
Boiling Point Elevation Sample Problems

What is the boiling point of a solution that contains 1.25 mol of calcium chloride in 1400 g of water? (Kb
of water = 0.512 °C/m)

What mass of NaCl would have to be dissolved in 1.00 kg of water to raise the boiling point by
2.00 °C?(Kb of water = 0.512 °C/m)
Freezing Point Depression



When a substance freezes, the particles take on an ______________________ _____________________
Adding a solute disrupts the formation of this orderly pattern by ______________________ the amount
of ______________________ that must be given off in order for freezing to occur than in the
______________________ solvent
The ______________________ particles of solute that are added, the ______________________ the
freezing point of the substance.
Freezing Point Depression Calculations
Equation:



ΔT = __________________________________
Kf = __________________________________
msolute = __________________________________
Freezing Point Depression Sample Problem
•
Antifreeze protects a car from freezing. It also protects it from overheating. Calculate the freezing point
of a solution containing 100.0 g of ethylene glycol (C2H6O2) antifreeze in 0.500 kg of water. (Kf of H2O
= 1.86˚C/m)
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