1. Chapter 21 Colligative Properties: Part 2

2. Colligative Properties Properties determined by the number of solute particles in solution rather than the type of particles.  Vapor pressure lowering  Boiling point elevation  Freezing point depression  Osmotic pressure

3. Boiling Point Elevation ∆T bp = (K bp )(m)(#particles)

5. Boiling Point Elevation ∆T bp = (K bp )(m)(#particles) # particles Molecular solutes always = 1 Example: C 6 H 12 O 6 Ionic solutes = # of ions in the compound Example: BaCl 2, Al 2 (SO 4 ) 3

6. Freezing Point Depression ∆T fp = (K fp )(m)(#particles)

8. Why is salt used on the roads instead of sugar?

10. What is the freezing point of a 1.5m aqueous solution of NaCl? ∆T fp = (K fp )(m)(#particles) ∆T fp = (1.853°C∙kg/mol)(1.5mol/kg)(2) ∆T fp = 5.559°C New Freezing Point = 0.000°C – 5.559°C FP = -5.559°C

12. What is the boiling point of a 2.4m aqueous solution Ba(NO 3 ) 2 ? BP = 103.708°C ∆T bp = (K b )(m)(#particles) ∆T bp = (0.515°C∙kg/mol)(2.4mol/kg)(3) ∆T bp = 3.708°C New Boiling Point = 100.000°C + 3.708°C

14. 97.5g of C 12 H 22 O 11 are dissolved in 185g of water. Find the freezing point and boiling point. FP = -2.854°C BP = 100.7931°C

15. 97.5g of C 12 H 22 O 11 are dissolved in 185g of water. Find the freezing point and boiling point. FP = -2.854°C BP = 100.7931°C A

16. 97.5g of C 12 H 22 O 11 are dissolved in 185g of water. Find the freezing point and boiling point. FP = -2.854°C BP = 100.7931°C A

17. 97.5g of C 12 H 22 O 11 are dissolved in 185g of water. Find the freezing point and boiling point. FP = -2.854°C BP = 100.7931°C A

18. 97.5g of C 12 H 22 O 11 are dissolved in 185g of water. Find the freezing point and boiling point. FP = -2.854°C BP = 100.7931°C A

19. 97.5g of C 12 H 22 O 11 are dissolved in 185g of water. Find the freezing point and boiling point. FP = -2.854°C BP = 100.7931°C

21. 14.0g of C 10 H 8 are dissolved in 25.0g of benzene. Find the freezing point and boiling point. FP = -16.867°C BP = 91.169°C

22. 14.0g of C 10 H 8 are dissolved in 25.0g of benzene. Find the freezing point and boiling point. FP = -16.867°C BP = 91.169°C A

24. 14.0g of C 10 H 8 are dissolved in 25.0g of benzene. Find the freezing point and boiling point. FP = -16.867°C BP = 91.169°C A

25. 14.0g of C 10 H 8 are dissolved in 25.0g of benzene. Find the freezing point and boiling point. FP = -16.867°C BP = 91.169°C A

26. 14.0g of C 10 H 8 are dissolved in 25.0g of benzene. Find the freezing point and boiling point. FP = -16.867°C BP = 91.169°C A

27. 14.0g of C 10 H 8 are dissolved in 25.0g of benzene. Find the freezing point and boiling point. FP = -16.867°C BP = 91.169°C

28. Homework Finish Worksheet: Vapor Pressure, Boiling Point and Freezing Point.