1. Solutions Chapter 12 Modern Chemistry
Sections 1-3
Types of Mixtures
The Solution Process
Concentrations of Solution
Chapter 12 Section 3 Concentration of Solutions p

2. Concentration of Solutions
Section 12.3
Concentration of Solutions
Chapter 12 Section 3 Concentration of Solns p

3. Chapter 12 Section 3 Concentration of Solns p. 418-424
Vocabulary
Concentration
Concentrated
Dilute
Molarity
Molality
Dilution
Chapter 12 Section 3 Concentration of Solns p

4. Chapter 12 Section 3 Concentration of Solns p. 418-424
CONCENTRATED
DILUTE
CONCENTRATION
MOLARITY
MOLALITY
DILUTIONS
Concept Map 12.3
Chapter 12 Section 3 Concentration of Solns p

5. Chapter 12 Section 3 Concentration of Solns p. 418-424
Concentration is a measure of the amount of solute in a given amount of solvent or solution.
Dilute means that there is a small amount of solute.
Concentration means that there is a large amount of solute.
There are many ways to quantify concentration.
Chapter 12 Section 3 Concentration of Solns p

6. Chapter 12 Section 3 Concentration of Solns p. 418-424
Concentration Units
Chapter 12 Section 3 Concentration of Solns p

7. Concentration & Molarity
Chapter 12 Section 3 Concentration of Solns p
p. xx

8. Chapter 12 Section 3 Concentration of Solns p. 418-424
Molarity
The number of moles of solute in one liter of solution.
moles of solute
M =
liters of solution
M =
mol L
Chapter 12 Section 3 Concentration of Solns p

9. Making a Molar Solution
Chapter 12 Section 3 Concentration of Solns p
p. 419

10. Making a Molar Solution
Insert Holt Disc 2
Chapter 12 Section 3 Concentration of Solns p
p. xx

11. Molarity Sample Problems
You have 3.50 L of solution that contains 90.0 g of sodium chloride, NaCl. What is the molarity of that solution?
You have 0.8 L of a 0.5 M HCl solution. How many moles of HCl does this solution contain?
To produce 40.0 g of silver chromate, you will need at least 23.4 g of potassium chromate in solution as a reactant. All you have on hand is 5 L of a 6.0 M K2CrO4 solution. What volume of the solution is needed to give you the 23.4 g K2CrO4 needed for the reaction?
M NaCl p
mol HCl
L K2CrO4
Chapter 12 Section 3 Concentration of Solns p

12. Molarity Practice Problems
What is the molarity of a solution composed of 5.85 g of potassium iodide, KI, dissolved in enough water to make L of solution?
How many moles of H2SO4 are present in L of a M H2SO4 solution?
What volume of 3.00 M NaCl is needed for a reaction that requires g of NaCl?
M KI
p. 421
mol L
Chapter 12 Section 3 Concentration of Solns p

13. Chapter 12 Section 3 Concentration of Solns p. 418-424
Molarity vs. Molality
Chapter 12 Section 3 Concentration of Solns p
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14. Chapter 12 Section 3 Concentration of Solns p. 418-424
Molality
The number of moles of solute per kilogram of solvent.
moles of solute
m =
kilograms of solvent
m =
mol Kg
The density of water is 1 g / mL. So, 1 g = 1 mL and 1kg = 1 L
Chapter 12 Section 3 Concentration of Solns p

15. Making a Molal Solution
Chapter 12 Section 3 Concentration of Solns p
p. 422

16. Molality Sample Problems
A solution was prepared by dissolving 17.1 g of sucrose (table sugar, C12H22O11) in 125 g of water. Find the molal concentration of this solution.
A solution of iodine, I2, in carbon tetrachloride, CCl4, is used when iodine is needed for certain chemical tests. How much iodine must be added to prepare a m solution of iodine in CCl4 if g of CCl4 is used?
m C12H22O11 p
g I2
Chapter 12 Section 3 Concentration of Solns p

17. Molality Practice Problems
What is the molality of acetone in a solution composed of 255 g of acetone, (CH3)2CO, dissolved in 200. g of water?
What quantity, in grams, of methanol, CH3OH, is required to prepare a m solution in 400. g of water?
m acetone
p. 424
g CH3OH
Chapter 12 Section 3 Concentration of Solns p

18. M1 V1 = M2 V2 Diluting a Solution
How much of an original solution is needed to make a less concentrated solution by adding water?
M1 V1 = M2 V2
Volume of New Solution Wanted
Original Molarity
Volume of Original Solution Needed
New Molarity
Chapter 12 Section 3 Concentration of Solns p

19. Chapter 12 Section 3 Concentration of Solns p. 418-424
Diluting a Solution
Insert Holt Disc 2
Chapter 12 Section 3 Concentration of Solns p
p. xx

20. Chapter 12 Section 3 Concentration of Solns p. 418-424
Dilution Problems
P. 902 # What is the molarity of a solution of ammonium chloride prepared by diluting mL of a 3.79 M NH4Cl solution to 2.00 L?
P. 903 #370. To what volume should 1.19 mL of an 8.00 M acetic acid solution be diluted in order to obtain a final solution that is M? M
6.35 mL
Chapter 12 Section 3 Concentration of Solns p

21. Chapter 12 Section 3 Concentration of Solns p. 418-424
Dilution Problems
P. 903 # What volume of a 5.75 M formic acid solution should be used to prepare 2.00 L of a 1.00 M formic acid solution?
P. 903 #372. A mL sample of ammonium nitrate solution produces a M solution when diluted with mL of water. What is the molarity of the stock solution?
348 mL
0.558 M
Chapter 12 Section 3 Concentration of Solns p

22. Chapter 12 Section 3 Concentration of Solns p. 418-424
Ch 12 Sec 3 Homework
Molarity, Molality, Dilution Problem Bank Page # , , 375
Chapter 12 Section 3 Concentration of Solns p