1. Colligative Properties

2. Colligative properties –

3. Colligative properties – Anytime a solute is dissolved in a solvent, the properties of the solvent are changed.

4. These changes are based on the number of particles dissolved, not the type of particle.

5. Colligative properties – Anytime a solute is dissolved in a solvent, the properties of the solvent are changed. These changes are based on the number of particles dissolved, not the type of particle. The van’t Hoff factor (i) takes the number of particle(s) into account. i = the number of particles in solution. NaCl(s)  Na 1+ (aq) + Cl 1- (aq)i = 2 C 6 H 12 O 6  C 6 H 12 O 6 i = 1

6. What is an electrolyte? Nonelectrolyte?

7. Electrolyte – a solute that when dissolved in a solution produces ions and it will conduct electricity. This could happen through dissociation or ionization. Nonelectrolyte – a solute that when dissolved in a solution does not produce ions and it will not conduct electricity.

8. Electrolyte – a solute that when dissolved in a solution produces ions and it will conduct electricity. This could happen through dissociation or ionization. Nonelectrolyte – a solute that when dissolved in a solution does not produce ions and it will not conduct electricity. Are the following electrolytes or nonelectrolytes? CaCl 2 C 6 H 12 O 6 HCl NH 4 Cl

9. Electrolyte – a solute that when dissolved in a solution produces ions and it will conduct electricity. This could happen through dissociation or ionization. Nonelectrolyte – a solute that when dissolved in a solution does not produce ions and it will not conduct electricity. Are the following electrolytes or nonelectrolytes? CaCl 2 C 6 H 12 O 6 HCl NH 4 Cl What would be the van’t Hoff factor for each of the above?

10. What does nonvolatile mean?

11. It does not evaporate easily. All of the solutes in this chapter are nonvolatile.

12. 1. What happens to the vapor pressure of the solvent, when a nonvolatile solute is added?

13. 1. Reduction of vapor pressure The higher the number of solute particles present, the lower the vapor pressure above the solution.

14. 1. Reduction of vapor pressure The higher the number of solute particles present, the lower the vapor pressure above the solution. Because fewer of the solvent particles turn into a gas, the vapor pressure lowers and the liquid phase exists over a larger temperature range.

15. 2. What happens to the freezing point of the solvent when a solute is added?

17. 2. Freezing point depression The higher the number of solute particles dissolved in the solvent, the lower the freezing point.

18. 2. Freezing point depression The higher the number of solute particles dissolved in the solvent, the lower the freezing point. Each solvent has a unique constant that its freezing point is lowered by for each mole of particles dissolved in a kilogram of solvent. P. 448

19. 2. Freezing point depression The higher the number of solute particles dissolved in the solvent, the lower the freezing point. Each solvent has a unique constant that its freezing point is lowered by for each mole of particles dissolved in a kilogram of solvent. P. 448 Water’s freezing point goes down by 1.86ºC for every mole of particles dissolved.

20. 2. Freezing point depression The higher the number of solute particles dissolved in the solvent, the lower the freezing point. Each solvent has a unique constant that its freezing point is lowered by for each mole of particles dissolved in a kilogram of solvent. P. 448 The change in the freezing point can be calculated using: Δt f = i K f m

21. 3. What happens to the boiling point of a solvent when a solute is added?

23. 3. Boiling point elevation The higher the number of solute particles dissolved in the solvent, the higher the boiling point.

24. 3. Boiling point elevation The higher the number of solute particles dissolved in the solvent, the higher the boiling point. Again, each solvent has a unique constant that its boiling point is elevated by for each mole of particles dissolved in a kilogram of solvent. P. 448 Water’s boiling point goes up by 0.51ºC for every mole of particles dissolved.

25. 3. Boiling point elevation The higher the number of solute particles dissolved in the solvent, the higher the boiling point. Again, each solvent has a unique constant that its boiling point is elevated by for each mole of particles dissolved in a kilogram of solvent. P. 448 The change in the boiling point can be calculated using: Δt b = i K b m

26. Example 1: What will be the new freezing point and boiling point of an aqueous solution containing 55.0g glycerol, C 3 H 5 (OH) 3, in 250g of water? Glycerol is a nonvolatile nonelectrolyte.

27. Example 2: How many grams of glucose, C 6 H 12 O 6, are required to lower the freezing point of 150g of H 2 O by 0.750ºC? Glucose does not dissociate in water.

28. Example 3: What would be the freezing point of a solution combining 5.13g of KBr in 255g of water?

29. What does this mean?

30. Using percent composition, change in freezing point or boiling point, and grams used, this can be used in the lab to determine a new compound formed.

31. Example 4: Lauryl alcohol (a nonelectrolyte) is obtained from coconut oil and is used to make detergents. A solution of 5.00g of lauryl alcohol in 0.100kg of benzene freezes at 4.1ºC. What is the molar mass of lauryl alcohol?

32. Example 5: What is the change in boiling point and freezing point if 3.69 g of K 2 SO 4 is added to 100.0 mL of water?

33. 4. What is osmosis? What is osmotic pressure?

34. 4. Osmotic Pressure Osmosis is the movement of a solvent through a semi permeable membrane.

35. 4. Osmotic Pressure Osmosis is the movement of a solvent through a semi permeable membrane. The solvent always moves from an area of high solvent concentration to an area of lower solvent concentration.

36. 4. Osmotic Pressure Osmosis is the movement of a solvent through a semi permeable membrane. The solvent always moves from an area of high solvent concentration to an area of lower solvent concentration. Osmotic pressure is the pressure that must be applied to stop osmosis from happening.

37. 4. Osmotic Pressure Osmosis is the movement of a solvent through a semi permeable membrane. The solvent always moves from an area of high solvent concentration to an area of lower solvent concentration. Osmotic pressure is the pressure that must be applied to stop osmosis from happening. The higher the number of solute particles dissolved in the solvent, the higher the osmotic pressure which must be applied to stop osmosis.

38. Tube is filled with water on one side and sucrose solution on the other. Water particles move to the right. As the sucrose solution increases in height it exerts a pressure against the water moving. If extra pressure is applied to the sucrose side, the water can be forced to move “backwards”.

39. REVERSE OSMOSIS FILTRATION

40. TIME RELEASE DRUG CAPSULE

41. CHAPTER 13 TEST 15 multiple choice (4 points each) 5 colligative property questions (5 points each) 5 writing net ionic equations (3 points each) 1 extra credit (5 points) Dissociation vs ionization Writing equations for both Precipitation reactions Writing net ionic equations Predicting precipitates Labeling spectator ions Electrolytes vs nonelectrolytes Weak vs strong electrolytes 4 colligative properties Vapor pressure reduction Boiling point elevation Freezing point depression Osmotic pressure

42. Calculate changes in boiling point or freezing point Calculate molar mass Calculate molality