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Unit 12: Name ______Chapter 12

Unit Learning Targets (L.T.): By the end of the unit, students will be able to:

1. Define and explain vocabulary 2. Compare and contrast Solutions, , and Suspensions 3. Understand and calculate Molarity, Molality and problems

Topic and L.T. Activities/Labs/In-class Work Homework*

Intro to Solutions Unit 12 Notes and Discussion: Review Part 2 Introduction to Solutions Unit 12 Quizlet Review Part 1 Due in Class Molarity and Molality Unit 12 Notes and Discussion: Molarity, Review Part 3 Independent Molality and Practice (and in-class if not Practice Problems: Molarity and Molality finished) Unit 12 Quizlet Molarity and Molality Quiz: Solution Vocabulary (Unit 12/ Finish Lab Chapter 12 on Quizlet) Additional Molarity and Molality Lab: KHP Lab Practice Problems on Blog Practice Problems: Molarity and Molality Unit Test Unit Test TBD

* Please note – Additional activities, labs, and homework may be added as necessary. Any changes discussed in class and written on the board should be added to homework listed above by the student and will be due as discussed in class.

Review Part 1: Solutions, Colloids and Suspensions

Learn Vocabulary using Quizlet Chem I Waukee Unit 12/Chapter 12 – Quiz in 2 days!

1. What is the difference between a , a and a solution?

2. What test or effect can be used to distinguish between a solution and a colloid?

3. List two examples of colloids and two examples of suspensions.

4. How do you identify which is the solute and which is the in solutions that are in the same phase? (for example a liquid – liquid solution like Mio drops in water)

5. Identify the solute and solvent in the following:

Air (78% Nitrogen and 21% Oxygen)

Cloud (water vapor in the atmosphere)

Salt water

Carbon dioxide in soda 6. Copy on another sheet and complete the following table:

Solutions Colloids Suspensions Type (Homogenous or heterogeneous) Particle Size

Separate on standing? Separated by filtration? Scatter Light?

7. What is the difference between an electrolyte and a non-electrolyte solution? Give an example of each in your answer.

Review Part 2: The Solution Process

1. What are the three changes you can make to speed up the solution process?

2. Explain, in your own words, “Solution Equilibrium.”

3. What is the difference between a saturated and an unsaturated solution?

4. You are given a beaker containing an unknown solute in water. You use the Tyndall effect to determine that it is in fact a solution. However, there is undissolved solute resting on the bottom of the beaker. This indicates that the solution is ______. Explain your answer.

5. What is the difference between a saturated and a supersaturated solution?

6. What is meant by the phrase “likes dissolve likes?” Provide examples in your answer.

7. Which would be more soluble in water (which is a polar solvent) BaCl2 or CF4? Explain

8. Explain immiscible. Use the term in a sentence you make up.

9. Explain miscible. Use the term in a sentence you make up.

10. Explain Henry’s Law. How does it apply to carbonated beverages? Why do they make a noise when you open the can?

Part 3: Molarity and Concentration

Learn Vocabulary using Quizlet Chem I Waukee Unit 12/Chapter 12 – Quiz in 2 days!

1. What is the difference between a dilute and a concentrated solution?

2. Explain, in your own words, how to determine the molarity of a solution.

3. Explain, in your own words, how to determine molality.

4. How are molality and molarity different? How are they similar?

5. How can you identify a problem as a Molarity problem?

6. How can you identify a problem as a Molarity problem?

7. Since both numbers may be grams in molality problems, how can you identify the solute and solvent?

8. What equation can you use when preparing a diluted solution (changing a solution from one molarity to another)?

In-Class Practice Problems:

1. Calculate the molarity of 35.0g MnSiF6 in 5000 mL of solution

2. Calculate the molarity of 0.273 moles of CoSO4 in .250 L of solution

3. Calculate the molality of a solution with 98.0 g RbBr in 824 g water

4. What is the molarity of a solution that has 145g (NH4)2C4H4O6 dissolved in 500 cm3 of solution?

5. Calculate the of solute neded to prepare LiMnO4 to be added to 500 g of water for a 0.614 m solution

6. Calculate the mass of solute needed to make100 ml of 0.05 M SrSiF6

7. Calculate the mass of solute needed to prepare Fe2(C2O4)3 to be added to 1000 g of water for a 0.851 m solutions?

8. Calculate amount of water needed to prepare 250 ml of 3M HCl if you start with 12M HCl?

Independent Practice Problems: Mixed Molarity/Molality Calculations

1. Gatorade Thirst Quencher has 23 mg of K+ in a 250 mL glass. What is the molarity of K+?

o 2. At 25 C, 1.40 grams of NaCl dissolves in enough methanol (CH3OH) to give 0.10 L of solution. What is the molarity of the solution?

3. What is the molality of a solution prepared by dissolving 5.00 g of chlorobenzene, C6H5Cl, in 115 g of benzene, C6H6?

4. Rubbing alcohol contains 595 g of isopropyl alcohol (C3H7OH) in 1.00 L of solution. What is the molarity of isopropyl alcohol?

5. Determine the number of moles of solute present in 2.50 mL of 0.1812 M KMnO4 solution.

6. How many moles of C6H5OH are required to prepare 250 mL of a 0.10 M solution?

7. Vanillin, C8H8O3, occurs in vanilla extract and is used as a flavoring agent, A 37.2 mg sample of vanillin is dissolved in 153.1 mg of diphenyl ether, (C6H5)2O. What is the molality of vanillin?

8. What (mL) of concentrated NH3 (14.8 M) should be used to prepare 200.0 mL of a 0.600 M NH3 solution?

9. How many grams of NaBr must be added to 850. g of water to make a 1.6 m solution?

10. Calculate the mass of solute needed to make 250 ml of 1.5 M AgF