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Chapter 14 Main Idea
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Chemistry- Matter and Change Chapter 14
Chapter 14.1 Types of Mixtures
Main Idea
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Objectives
      Compare the properties of suspensions, colloids and solutions
      Identify the types of colloids and types of solutions
      Describe the electrostatic forces in colloids
      Predict whether a solution is an electrolyte or nonelectrolyte
      Test your prediction
Review Vocabulary
      Solute

      Solvent

      Molar mass

      Concentration

New Vocabulary
      Suspension

      Colloid

      Brownian motion

      Tyndall effect

      Soluble

      Miscible

      Insoluble

      Immiscible

      Electrolyte

      Nonelectrolyte
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Chemistry- Matter and Change Chapter 14
Heterogeneous mixtures



Suspensions



Colloids




                                            Solute

                              Solid              Liquid              Gas

           Solid            Solid sol     Solid emulsion or gel   Solid foam
 Solvent




           Liquid              Sol             Emulsion             Foam

            Gas           Solid aerosol      Liquid aerosol



Brownian Motion



Tyndall Effect



Homogeneous mixtures



Forming solutions




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Chemistry- Matter and Change Chapter 14
Electrolytes and Nonelectrolytes

Electrolyte                                              Nonelectrolyte




Draw a diagram of an instrument you could use to see if a solution is an electrolyte.




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Chemistry- Matter and Change Chapter 14
14.2 Solution Concentration

14.2 Main Idea
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14.2 Objectives
      Describe concentration using different units

      Determine the concentration of solutions

      Calculate the molarity of a solution

      Prepare different solutions with given molarity, percent by mass, percent by volume, molality,
       and mole ratio.

Review Vocabulary
      Solvent

      Ratio

      Mass

      Mole

New Vocabulary
      Concentration

      Molarity

      Molality

      Mole fraction

      Dilution

Solve (Show work!)
What is the mass of 1.25 mol oxygen gas?

What is the volume of 2.00 mol hydrogen gas at STP?


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Chemistry- Matter and Change Chapter 14
  Concentration
                                                      Ratio
   Description

  Percent by mass


Percent by volume


       Molarity


       Molality


   Mole fraction



Percent by mass



In order to maintain a sodium chloride concentration similar to ocean water, an aquarium must contain
3.6 g sodium chloride per 100.0 g of water. What is the percent by mass of NaCl in the solution?




Percent by volume



What is the percent by volume of ethanol in a solution that contains 35mL of ethanol distributed in
155mL of water?




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Chemistry- Matter and Change Chapter 14
Molarity




You have 3.50 L of solution that contains 90.0 g of sodium chloride, NaCl. What is the molarity of that
solution?




Dilutions of molar solutions



What volume in milliliters, of a 2.00M calcium chloride stock solution would you use to make 0.50 L of
0.300M calcium chloride solution?




Molality




In the lab, a student adds 4.5 g of sodium chloride to 100.0 g of water. Calculate the molality of the
solution.




Mole Fraction

A hydrochloric acid solution contains 36g HCl and 64g H2O. What is the mole fraction for the solution?




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Chemistry- Matter and Change Chapter 14
14.3 Factors Affecting Solvation
14.3 Main Idea
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14.3 Objectives
      Describe how intermolecular forces affect solvation
      Define solubility
      Predict how different factors affect solubility
      Create solutions that are unsaturated, saturated and super-saturated
14.3 Review Vocabulary
      Exothermic

      Endothermic

      Solution

      Polarity

      Ionic bond

      Covalent bond

      Ionization

14.3 New Vocabulary
      Solvation

      Heat of solution

      Unsaturated solution

      Saturated solution

      Supersaturated solution

      Henry’s law

      Dissociation

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Chemistry- Matter and Change Chapter 14
The solvation process




Solvation of ionic compounds




Solvation of molecular compounds




Heat of solution



Factors that affect the rate of solvation



Degrees of solubility



   Saturated                       Unsaturated   Supersaturated




Solubility of gases




Henry’s Law



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Chemistry- Matter and Change Chapter 14
14.4 Colligative Properties of Solutions
14.4 Main Idea
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14.4 Objectives
       Describe colligative properties

       Identify four colligative properties of solutions

       Determine the boiling point elevation and freezing point depression of a solution

14.4 Review Vocabulary
       Ion

       Boiling point

       Freezing point

14.4 New Vocabulary
       Colligative property

       Vapor pressure lowering

       Boiling point elevation

       Freezing point depression

       Osmosis

Solve
What is the molarity of a 500 ml solution that contains 35.5 g of sodium chloride?




In a closed system, 5.0 L of gas is heated from 0° C to 100°C, what is the new volume of the gas?



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Chemistry- Matter and Change Chapter 14
Electrolytes and colligative properties




Vapor pressure lowering




Boiling point elevation




Freezing point depression




Sodium chloride is often used to prevent icy roads and to freeze ice cream. What are the boiling and
freezing points of a 0.029m aqueous solution of sodium chloride?




Osmosis




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Chemistry- Matter and Change Chapter 14
Types of Mixtures Worksheet
                               Suspension                  Colloid                    Solution

  Heterogeneous or
   homogeneous?
    Particle size

       Settles?

      Filtered?

    Scatters light?



Match the terms with the descriptions

   1.________          Solid sol                          A.    Gas dissolved in liquid
   2.________          Solid emulsion                     B.    Gas dissolved in solid
   3.________          Solid foam                         C.    Liquid dissolved in gas
   4.________          Sol                                D.    Liquid dissolved in liquid
   5.________          Emulsion                           E.    Liquid dissolved in solid
   6.________          Foam                               F.    Solid dissolved in gas
   7.________          Solid aerosol                      G.    Solid dissolved in liquid
   8.________          Liquid aerosol                     H.    Solid dissolved in solid
Compare and contrast a mixture with a solution

Compare/Contrast
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Fill in the missing words.

Solutions that have water as a solvent are _____________________ solutions.
Solutions can consist of solutes and solvents that are ____________, _______________, or __________.
__________________ scatter light that is shined through them.
Solutions are ___________________ mixtures.

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Chemistry- Matter and Change Chapter 14
Electrolytes worksheet
Directions: Use the words provided to fill in the blank spaces below.
water                     positive        electrolyte              negative        move
sugar                     neutral         Nonelectrolyte           ions            sodium chloride
electric charge


   1. Substances that dissolve in water are classified according to whether they produce molecules or
         ___________in solution.
   2. When an ionic compound dissolves, the ____________ and ____________ ions separate from
         each other and are surrounded by ________________molecules.
   3. These solute ions are free to___________, making it possible for an __________________ to
         pass through the solution.
   4. A substance that dissolves in water to give a solution that conducts electric current is called an
         __________________.
   5. ____________________is an example of an electrolyte.
   6. A solutions containing _________ solute molecules does not conduct electric current because it
         does not contain mobile charged particles.
   7. A substance that dissolves in water to give a solution that does not conduct an electric current is
         called a ____________________.
   8. _________________ is an example of a nonelectrolyte


Complete the following table
Solution              Cation          Cation        Anion           Anion         Total Ion
Concentration         Formed          Concentration Formed          Concentration Concentration
1.0 M NaCl
1.0 M AlCl3
2.0 M NaOH
2.0 M MgBr2
0.10 M                     K+                               Cl-
                           K+                              SO42-                        0.30 M
0.10 M K3PO4
                           Li+          0.50 M              Cl-                         1.00 M
                               2+                             -
0.50 M                    Ca                                Cl
0.50 M C6H6O6
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Chemistry- Matter and Change Chapter 14
The Nature of Solutions
1. What is the difference between a strong electrolyte and a weak electrolyte?


2. Compare and contrast dissociation and ionization.




Predict whether the following substances will be soluble or insoluble when mixed.
3. water and methanol (CH3OH)
4. wax and CCl4


5. You have a flask containing a solution of NaCl. How could you determine whether the
   solution is saturated or unsaturated?




Use the solubility curve to answer questions 6 – 9.
6. How many grams of potassium nitrate can dissolve in 100 g
   of water at 50C?


7. At 20C, a solution contains 120 g of NaNO3 in 100 g of
   water. Is this solution saturated, unsaturated, or
   supersaturated?


8. You need to make a solution containing 150 g of potassium
   chloride in 300 g of water. What temperature is required?


9. What is the difference between the curves showing an
   increase in solubility and those showing a decrease?


10. Fish “breathe” by absorbing oxygen gas that is dissolved in water. Thermal pollution is
    caused when the temperature of the water in lakes and streams increases due to warm
    water output from power plants. Explain why thermal pollution is harmful to the fish
    population.




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Chemistry- Matter and Change Chapter 14
11. Explain why a bottle of soda fizzes when you first open it.


Electrolytes and Colloids Worksheet
1)     Explain why an aqueous solution of a strong electrolyte would conduct electricity better
       than an aqueous solution of a weak electrolyte.




2)     Which would conduct electricity better, a molten strong electrolyte or a molten weak
       electrolyte? Explain.




3)     What is the percent composition of water in magnesium sulfate heptahydrate?




4)     Why do hygroscopic compounds absorb water from the air?




5)     Why do the particles in a colloid stay suspended in a liquid, while the particles in a
       suspension settle out?




7)     How does the Tyndall effect work?




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Chemistry- Matter and Change Chapter 14
Molarity Worksheet (2 pages)
     n                Solve for n                     Solve for V
       M
     V
                      n=                              V=

1)     How many grams of potassium carbonate are needed to make 200 mL of a 2.5 M solution? 69.1
       grams



2)     How many liters of water are needed to make a 4 M solution using 100 grams of lithium
       bromide? 3.47 L



3)     What is the concentration of a solution that contains 450 mL of water and 200 grams of iron (II)
       chloride? 3.51 M



4)     How many grams of ammonium sulfate are needed to make a 0.25 M solution at a
       concentration of 6 M? 171.2 grams



5)     What is the concentration of a solution that contains 2.5 L of solvent and 660 grams of calcium
       phosphate? 0.85 M



6)     How many grams of copper (II) fluoride are needed to make 6.7 liters of a 1.2 M solution?
       1081.4 grams



7)     How many liters of solvent are required to make a 0.88 M solution using 25.5 grams of lithium
       fluoride? 1.11 L



8)     What is the concentration of a solution that contains 660 mL of solvent and 33.4 grams of
       aluminum acetate? 0.25 M

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Chemistry- Matter and Change Chapter 14
9)     How many liters of water are needed to make a 0.75 M solution using 75 grams of lead (II)
       oxide? 12.6 grams



10)    How many grams of manganese (IV) oxide are needed to make a 5.6 liters of a 2.1 M solution?
       1021.9 grams



11)    What is the concentration of a solution that contains 9 mL of solvent and 2 grams of iron (III)
       hydroxide? 2.08 M



12)    How many liters of water are required to make a 3.4 M solution using 78 grams of isopropanol
       (C3H8O)? 0.41 L



13)    What is the concentration of a solution containing 3.3 mL of solvent and 12 grams of ammonium
       sulfite? 31.3 M




Molality Worksheet
1)     What is the molality of a solution containing 7.8 g of MgCl2 in 725 g of water? 0.114 molal




2)     How many grams of ethanol, C2H5OH, are required to make a 7.1m solution using 160.0
       g of water? 50.7 grams




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Chemistry- Matter and Change Chapter 14
More Molarity Practice
Calculate the molarities of the following solutions:
1)      2.3 moles of sodium chloride in 0.45 liters of solution. 5.11 M

2)      1.2 moles of calcium carbonate in 1.22 liters of solution. 0.98 M

3)      0.09 moles of sodium sulfate in 12 mL of solution. 7.5 M

4)      0.75 moles of lithium fluoride in 65 mL of solution. 11.5 M

5)      0.8 moles of magnesium acetate in 5 liters of solution. 0.16 M

6)      120 grams of calcium nitrite in 240 mL of solution. 3.79 M

7)      98 grams of sodium hydroxide in 2.2 liters of solution. 1.11 M

8)      1.2 grams of hydrochloric acid in 25 mL of solution. 1.35 M

9)      45 grams of ammonia in 0.75 L of solution. 3.53 M

Explain how you would make the following solutions.

10)     2 L of 6 M HCl Dissolve 426 g HCl, dilute to 2 L

11)     1.5 L of 2 M NaOH Dissolve 120 g NaOH, dilute to 1.5 L

12)     0.75 L of 0.25 M Na2SO4 Dissolve 26.64 g Na2SO4, dilute to 0.75 L

13)     45 mL of 0.12 M sodium carbonate Dissolve 0.57 g Na2CO3, dilute to 45 mL

14)     250 mL of 0.75 M lithium nitrite Dissolve 9.92 g LiNO2, dilute to 250 mL

15)     56 mL of 1.1 M iron (II) phosphate Dissolve 22.02 g Fe3(PO4)2, dilute to 56 mL

16)     6.7 L of 4.5 M ammonium nitrate Dissolve 2412 g NH4NO3, dilute to 6.7 L

17)     4.5 mL of 0.05 M magnesium sulfate Dissolve 0.02709 g MgSO4, dilute to 4.5 mL

18)     90 mL of 1.2 M BF3 Dissolve 7.32 g BF3, dilute to 90 mL




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Chemistry- Matter and Change Chapter 14
Dilutions Worksheet
1)     If I have 340 mL of a 0.5 M NaBr solution, what will the concentration be if I add 560 mL
       more water to it? 0.19 M (the final volume is 900 mL, set up the equation from that)




2)     If I dilute 250 mL of 0.10 M lithium acetate solution to a volume of 750 mL, what will the
       concentration of this solution be? 0.033 M (the final volume is 750 mL, set up the
       equation from that. Note that the phrasing difference between problems 1 and 2
       makes a big difference in the final answer).




3)     If I leave 750 mL of 0.50 M sodium chloride solution uncovered on a windowsill and 150
       mL of the solvent evaporates, what will the new concentration of the sodium chloride
       solution be? 0.63 M (this is the opposite of a dilutions problem – the V2 value is
       smaller than V1, but otherwise the equation is no different.)




4)     To what volume would I need to add water to the evaporated solution in problem 3 to get
       a solution with a concentration of 0.25 M? 1500 mL




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Chemistry- Matter and Change Chapter 14
Concentration Practice Worksheet
1)     If I make a solution by adding water to 75 mL of ethanol until the total volume of the solution is
       375 mL, what’s the percent by volume of ethanol in the solution? 20%




2)     If I add 1.65 L of water to 112 grams of sodium acetate…

       a)      What is the molality of NaC2H3O2 in this solution? 0.82 m




       b)      What is the percent by mass of sodium acetate in this solution? 6.36%




       c)      What is the mole fraction of water in this solution? 0.985




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Chemistry- Matter and Change Chapter 14
Solvation Worksheet
Fill in the missing words.
The solubility of a substance depends on the ___________________________.

The solubility of gases in liquids __________________ as temperature increases.

The solubility of solids in liquids increases as temperature __________________.

The solubility of gases in liquids __________ as pressure decreases.


Draw basic solubility curves for a solid and a gas. Label each line.




                                        Temperature




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Chemistry- Matter and Change Chapter 14
Colligative Properties Worksheet
1. Indicate how many particles are formed when the following solutes dissolve.
               SOLUTE              # OF PARTICLES                 SOLUTE                # OF PARTICLES

    sucrose (C12H22O11)                               magnesium chloride (MgCl2)

    sodium sulfate (Na2SO4)                           methanol (CH3OH)

2. When 5.0 g of CaCl2 dissolves in 50.0 g of water, what is the boiling point of the solution?




3. Find the boiling point of a solution containing 6.0 g benzene, C6H6, in 35 g of napthalene.




4. Mrs. K’s feet are aching at the end of a long day. At home, she dissolves 26.0 g of Epsom
   salt, MgSO4, in 1.5 kg of water. What is the freezing point of this solution?




5. Salt is often used to remove ice from roads and sidewalks. Explain how this process works
   in terms of colligative properties.




6. Which salt, NaCl or CaCl2, has a greater effect on freezing point? Explain.




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Chemistry- Matter and Change Chapter 14
    Review Worksheet (4 pages)
    1)   Explain why water is polar.




    2) What is the significance of the statement “like dissolves like”? What does “like” refer to?




    3) Identify the solvent and the solute in vinegar, a dilute aqueous solution of acetic acid.




    4) Write a chemical equation showing how calcium chloride dissolves in water.




    5) Which of the following substance dissolve in water? Explain your answer in terms of polarity.
       a. CH4                     b. KCl                          c. He


         d. MgSO4                    e. C6H12O6                        d. NaHCO3



    6) What is the basis for distinguishing among solutions, colloids, and suspensions?



    7) Complete the table on the electrolytes worksheet.


Use the chart on the next page to answer the next few questions.



    8) Which substance is most soluble at 60º C ?




    9) Which two substances have the same solubility at 80º C ?



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    Chemistry- Matter and Change Chapter 14
10) Which substance’s solubility changes the most
       from 0º C to 100º C ?




11) Which substance’s solubility changes the least
      from 0º C to 100º C ?


12) What is the solubility of potassium nitrate at
      90º C ?




13) At what temperature does potassium iodide
        have a solubility of 150 g/ 100 cm3 water ?



14) You have a solution of sodium nitrate
       containing 140 g at 65º C. Is the solution
       saturated, unsaturated, or supersaturated ?




15) You have a solution of potassium chlorate containing 4 g at 65º C. How many additional grams of
       solute must be added to it, to make the solution saturated ?




16) Calculate the molarity, M, of the following solutions:
            a. 3.0 moles of NaCl are dissolved in 1 liter of solution.




            b. 0.5 moles of MgF2 are dissolved in 2 liters of solution.




            c. 3 moles of NaOH are dissolved in 0.25 liters of solution.
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Chemistry- Matter and Change Chapter 14
   17) How many liters of a 4.0 M CaCl2 solution would contain 2 moles of CaCl2?




   18) How many liters of a 0.5 M CaCl2 solution would contain 3.5 moles of CaCl2?




   19) How many liters of a 2.5 M CaCl2 solution would contain 1.0 mole of CaCl2?




   20) How many moles of KCl are there in 2 liters of a 3.0 M solution?




   21) What is the molarity, M, of a solution in which 116 grams of KF are dissolved in 2 liters of
       solution?




   22) How many grams of KF are in 2 liters of a 3.0 M solution of KF? What is the [CaF2(aq)] of a
       solution when 39 g of CaF2 are dissolved in enough water to make 2200 mL of solution? ([ ] is
       how chemists say concentration or molarity)




   23) How many grams of NH3 are dissolved in 85 mL of a 0.75 M solution?




   24) 25 mL of 5.6 M HCl are placed in a volumetric flask. The flask is filled to 250 mL with water.
       What is the molarity of the new solution?




   25) 5.6 mL of NaOH are added to a flask and the flask is filled with water to the 200 mL mark. The
       concentration of the new solution is found to be .098 M. What was the initial molarity of the
       solution before the dilution was completed?

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Chemistry- Matter and Change Chapter 14
   26) A chemist has 300 mL of a 2.5 M KCl solution. The solution is diluted by adding 1.2 L of water
       to the original volume. What is the [KCl] of the diluted solution?




   27) A chemist has 2 liters of a 3.2 M hydrochloric acid solution. If the solution is left out in the room
       and enough water evaporates so that there is only 1.2 liters of solution left, what is the final
       molarity of this concentrated acid?




   28) When a chemist adds 1.0 L of water to 3.0 liters of a 0.8 M HF solution, what is the new
       concentration of the total HF solution?


   29) How much water will a chemist need to add to 200 mL of a 3.3 M KCl solution if they want to
       make a 1.0 M solution of KCl?




   30) Define each of the following vocabulary terms


          colligative property

          boiling point elevation

          freezing point depression

          Molality


   31) What is the molality when 3.54 grams of glucose (C6H12O6) is dissolved in 400 grams of water?




   32) How many kilograms of water must be added to 15.0 g of oxalic acid, H2C2O4, to prepare a 0.025
       m solution?




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Chemistry- Matter and Change Chapter 14

				
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