1. Chapter 10 Liquids and Solids

2. Chapter 10 Table of Contents Copyright © Cengage Learning. All rights reserved 2 10.1 Intermolecular Forces 10.2 The Liquid State 10.3 An Introduction to Structures and Types of Solids 10.4 Structure and Bonding in Metals 10.5 Carbon and Silicon: Network Atomic Solids 10.6Molecular Solids 10.7Ionic Solids 10.8Vapor Pressure and Changes of State 10.9Phase Diagrams

3. Section 10.1 Intermolecular Forces Return to TOC 1.To learn about hydrogen bonding, dipole-dipole, and London dispersion forces (van der Waals) 2.To understand the effect of intermolecular forces on the properties of liquids 3.To learn about interactions among water molecules 4.To predict relative physical properties based on intermolecular forces of attraction Objectives

4. Section 10.1 Intermolecular Forces Return to TOC A. Intermolecular Forces Low density Highly compressible Fill container Reviewing what we know (Lawnmower Engine) GasesSolids High density Slightly compressible (Bottle Pop) Rigid (keeps its shape)

5. Section 10.1 Intermolecular Forces Return to TOC Intermolecular forces – occur between molecules Intramolecular forces – occur inside the molecules (bonds)

6. Section 10.1 Intermolecular Forces Return to TOC Hydrogen Bonding (STRONGEST OF 3) Highly Magnetic Highly Polar Molecule (Not really a Bond) (Adhesion disk demo) Occurs between H and highly electronegative atom For example H-N, H-O, H-F bond

7. Section 10.1 Intermolecular Forces Return to TOC Dipole – Dipole attraction (Middle Strength) Permanent Magnetic Properties related to molecular dipole moment Polar Molecules

8. Section 10.1 Intermolecular Forces Return to TOC London Dispersion Forces (van der Waals) Weakest-sometimes magnet-NonPolar Molecules Formation of instantaneous dipoles by location of electrons in orbital

9. Section 10.1 Intermolecular Forces Return to TOC A. Intermolecular Forces Fond in Nonpolar molecules London Dispersion Forces (van der Waals)

10. Section 10.1 Intermolecular Forces Return to TOC A. Intermolecular Forces The nature of intermolecular forces is the same as the nature of intramolecular forces (bonds) – only to a varying degree. Intermolecular forces of attraction are a weaker part of the continuum of magnetic attractive forces that include chemical bonding. Weaker (Inter) (Intra) Stronger ______________________________________ VDW D-D H-Bond Covalent Polar Ionic

11. Section 10.1 Intermolecular Forces Return to TOC A. Intermolecular Forces H bonding molecules will exhibit all 3 intermolecular forces of attraction H Bonding forces will be the dominate D-D molecules will exhibit D-D and vdW vdW only vdW https://rumble.com/v2ze3j-space-station- astronauts-grow-a-water-bubble.htmlhttps://rumble.com/v2ze3j-space-station- astronauts-grow-a-water-bubble.html

12. Section 10.1 Intermolecular Forces Return to TOC A. Intermolecular Forces Become stronger as the sizes of atoms or molecules increase ---WHY? As atomic size increases, what else increases in number? How would this affect the ability of the molecules to pull together? FP? London Dispersion Forces

13. Section 10.1 Intermolecular Forces Return to TOC A. Intermolecular Forces Affects physical properties –Boiling point –Which molecule has the strongest Intermolecular forces of attraction? Why? Hydrogen Bonding

14. Section 10.1 Intermolecular Forces Return to TOC A. Intermolecular Forces Pour CH 3 OH vs H 2 O on tabletop The strength of intermolecular forces of attraction and the ability of the molecules to hold together directly affect the temperature at which substances melt (or freeze) and boil (or condense). See the Heating Curve…Explain on a molecular level what happens during the solid/liquid and liquid/gas phase change…..

15. Section 10.1 Intermolecular Forces Return to TOC B. Water and Its Phase Changes Heating/cooling curve

16. Section 10.1 Intermolecular Forces Return to TOC B. Water and Its Phase Changes Normal boiling point – at 1 atm = 100 o C Normal freezing point – at 1 atm = 0 o C Density –Liquid = 1.00 g/mL –Solid = 0.917 g/mL –Density differs because of the H-bonding effect at lower temps (lattice) (vdW, DD, H videos)

17. Section 10.1 Intermolecular Forces Return to TOC B. Summary of IMF Forces VDWDipole – DipoleH-Bonding sometimes Magnet Non Polar Weak IMF Low BP

18. Section 10.1 Intermolecular Forces Return to TOC B. Water and Its Phase Changes Let’s consider what happens on a molecular level when a substance changes phase from solid to liquid and liquid to gas. Motion, space between molecules, forces to overcome? Changes of state video Thoughts on boiling water at room temperature? Thoughts only!!

19. Section 10.1 Intermolecular Forces Return to TOC B. Water and Its Phase Changes As the strength of the intermolecular forces increases: The Boiling Point increases The Vapor Pressure decreases The Freezing Point increases

20. Section 10.1 Intermolecular Forces Return to TOC B. Predicting Relative Physical Properties Which of the following substances would have the higher boiling point? (Think polarity) NH 3 or BCl 3 CH 4 or CH 3 Cl H 2 O or H 2 S HF or HCl Which would have the highest freezing point? Vapor Pressure?

21. Section 10.1 Intermolecular Forces Return to TOC B. Predicting Relative Physical Properties

22. Section 10.1 Intermolecular Forces Return to TOC

23. Section 10.1 Intermolecular Forces Return to TOC

24. Section 10.1 Intermolecular Forces Return to TOC

25. Section 10.1 Intermolecular Forces Return to TOC 1.To learn about hydrogen bonding, dipole-dipole, and London dispersion forces (van der Waals) 2.To understand the effect of intermolecular forces on the properties of liquids 3.To learn about interactions among water molecules 4.To predict relative physical properties based on intermolecular forces of attraction 5.Work Session: Page 475 #29,31,33,35,37,39 (only work session) Objectives Review

26. Section 10.1 Intermolecular Forces Return to TOC To understand and use heat of fusion and heat of vaporization To derive formulas To use the 5 Step Method to find solutions using multiple equations Objectives

27. Section 10.1 Intermolecular Forces Return to TOC C. Energy Requirements for the Changes of State Changes of state are physical changes –No chemical bonds are broken

28. Section 10.1 Intermolecular Forces Return to TOC C. Energy Requirements for the Changes of State Molar heat of fusion – energy required to melt (S-L) 1 mol of a substance Molar heat of vaporization – energy required to change 1 mol of a liquid to its vapor …units of both??

29. Section 10.1 Intermolecular Forces Return to TOC C. Energy Requirements for the Changes of State If the molar heat of fusion of ice is 6.02 kJ/mol, how much energy is required to melt 9.54 g of ice at 0 o C? Can we derive the formula? Q = (molar heat of fusion kJ/mol)(mol) Q = fusion = mol =

30. Section 10.1 Intermolecular Forces Return to TOC C. Energy Requirements for the Changes of State If the molar heat of fusion of ice is 6.02 kJ/mol, how much energy is required to melt 9.54 g of ice at 0 o C? Q = (molar heat of fusion kJ/mol)(mol) Q = ? fusion = 6.02 kJ/mol mol = 9.54 g = mol Q = (6.02 kJ/mol)(0.53mol) = 3.19 kJ

31. Section 10.1 Intermolecular Forces Return to TOC C. Energy Requirements for the Changes of State Calculate the heat required to raise 9.54 g of liquid water from a temperature of 0 o C to 80 o C? The specific heat capacity of liquid water is 4.18. Q = ms  T Q = ? m = 9.54 g s = 4.18  T = (80 – 0) o C

32. Section 10.1 Intermolecular Forces Return to TOC C. Energy Requirements for the Changes of State Calculate the heat required to raise 9.54 g of liquid water from a temperature of 0 o C to 80 o C? The specific heat capacity of liquid water is 4.18. Q = ms  T Q = (9.54 g) (4.18 )(80 – 0) o C Q = 3190.18 J = 3.19 kJ Same Q to change phase S-L as to heat 80 o C!

33. Section 10.1 Intermolecular Forces Return to TOC C. Energy Requirements for the Changes of State Calculate the energy (kJ) required to heat 25 g of liquid water from 25 o C to 100 o C and change it to steam at 100 o C. The specific heat capacity of liquid water is 4.18, and the molar heat of vaporization of water is 40.6 kJ/mol. _____________________________________ Make a mental map- what is the essential Q? Gather what you know- formulas, constants? Unit analysis-conceptual logic, what’s going on?

34. Section 10.1 Intermolecular Forces Return to TOC C. Energy Requirements for the Changes of State Calculate the energy (kJ) required to heat 25 g of liquid water from 25 o C to 100 o C and change it to steam at 100 o C. The specific heat capacity of liquid water is 4.18, and the molar heat of vaporization of water is 40.6 kJ/mol. Energy in kJ to take Liq from 25 o C to steam at 100 o C 1) Warm w/o phase change 2) phase change Two formulas, two thermodynamic properties

35. Section 10.1 Intermolecular Forces Return to TOC C. Energy Requirements for the Changes of State Calculate the energy (kJ) required to heat 25 g of liquid water from 25 o C to 100 o C and change it to steam at 100 o C. The specific heat capacity of liquid water is 4.18, and the molar heat of vaporization of water is 40.6 kJ/mol. 1) Warm: Q = ms  T Q = m = s =  T =

36. Section 10.1 Intermolecular Forces Return to TOC C. Energy Requirements for the Changes of State 1) Warm: Q = ms  T Q = ? m = 25 g s = 4.18  T = (100 – 25) o C Q = ms  T = (25 g)(4.18 )(75 o C) = 7.8 X 10 3 J 7800 J = kJ 7.8 kJ Warm only……

37. Section 10.1 Intermolecular Forces Return to TOC Calculate the energy (kJ) required to heat 25 g of liquid water from 25 o C to 100 o C and change it to steam at 100 o C. The specific heat capacity of liquid water is 4.18, and the molar heat of vaporization of water is 40.6 kJ/mol. 2) Phase change Q = (molar heat of vap kJ/mol)(mol) Q = ? vap = 40.6 kJ/mol mol = 25 g = mol Q = (40.6 kJ/mol)(1.39 mol) = 56.43 kJ

38. Section 10.1 Intermolecular Forces Return to TOC C. Energy Requirements for the Changes of State Calculate the energy (kJ) required to heat 25 g of liquid water from 25 o C to 100 o C and change it to steam at 100 o C. The specific heat capacity of liquid water is 4.18, and the molar heat of vaporization of water is 40.6 kJ/mol. 1) Warm= 7.8 kJ 2) Phase change = 56.43 kJ Total ------------------ = 64.23 kJ Notice that most of the energy is required for the phase change event.

39. Section 10.1 Intermolecular Forces Return to TOC C. Energy Requirements for the Changes of State molar heat of vaporization of water is 40.6 kJ/mol molar heat of fusion of water is 6.02 kJ/mol Does it take more energy to melt ice or boil liquid? Why?

40. Section 10.1 Intermolecular Forces Return to TOC To understand and use heat of fusion and heat of vaporization To derive formulas To use the 5 Step Method to find solutions using multiple equations Objectives Review

41. Section 10.1 Intermolecular Forces Return to TOC 1.To understand the relationship among vaporization, condensation and vapor pressure 2.To relate the boiling point of water to its vapor pressure 3.To predict relative physical properties based on intermolecular forces of attraction Objectives

42. Section 10.1 Intermolecular Forces Return to TOC A. Evaporation and Vapor Pressure Vaporization or evaporation – individual molecules gain enough energy to change phase –Endothermic – requires heat input (Sanitizer)

43. Section 10.1 Intermolecular Forces Return to TOC A. Evaporation and Vapor Pressure Amount of liquid first decreases then becomes constant - H 2 O bottle Condensation - process by which vapor molecules convert to a liquid When no further change is visible the opposing processes balance each other - equilibrium Vapor Pressure

44. Section 10.1 Intermolecular Forces Return to TOC A. Evaporation and Vapor Pressure Vapor pressure - pressure of the vapor present at equilibrium with its liquid Vapor Pressure Vapor pressures vary widely - relates to intermolecular forces

45. Section 10.1 Intermolecular Forces Return to TOC 1.Vapor pressure - pressure of the vapor present at equilibrium with its liquid- relates to intermolecular forces 2.Molecules with higher intermolecular forces of attraction will have ________ vapor pressures because _________________________. lower, molecules will hold together more. A. Evaporation and Vapor Pressure

46. Section 10.1 Intermolecular Forces Return to TOC A. Evaporation and Vapor Pressure Which of the following substances would have the higher vapor pressure? Why? NH 3 or BF 3 CH 4 or CH 2 Cl 2 H 2 O or CH 3 OH (methyl alcohol) CH 3 OH or CH 3 CH 2 CH 2 CH 2 OH (butyl alc) What is the BP of methyl alcohol? Butyl alc? MA 67.7 C BA 82.2 C Vapor Pressure

47. Section 10.1 Intermolecular Forces Return to TOC B. Boiling Point and Vapor Pressure

48. Section 10.1 Intermolecular Forces Return to TOC B. Boiling Point and Vapor Pressure

49. Section 10.1 Intermolecular Forces Return to TOC B. Boiling Point and Vapor Pressure Boiling point is defined as occurring when the vapor pressure of the liquid is equal to the total external pressure (atmospheric pressure). Not defined by temperature! Boil water at room temp?? Boiling water with ice video

50. Section 10.1 Intermolecular Forces Return to TOC B. Boiling Point and Vapor Pressure Which of the following substances would have the higher boiling point? Why? GeH 4 or AsH 3 CCl 4 or H 2 Te CO 2 or H 2 S HF or HBr The amazing floating steel!

51. Section 10.1 Intermolecular Forces Return to TOC 1.To understand the relationship among vaporization, condensation and vapor pressure 2.To relate the boiling point of water to its vapor pressure 3.To predict relative physical properties based on intermolecular forces of attraction Objectives Review

52. Section 10.1 Intermolecular Forces Return to TOC 1.To learn about the types of crystalline solids 2.To understand the interparticle forces in crystalline solids 3.To learn how the bonding in metals determines metallic properties Objectives

53. Section 10.1 Intermolecular Forces Return to TOC A. The Solid State: Types of Solids Crystalline solids

54. Section 10.1 Intermolecular Forces Return to TOC A. The Solid State: Types of Solids

55. Section 10.1 Intermolecular Forces Return to TOC A. The Solid State: Types of Solids

56. Section 10.1 Intermolecular Forces Return to TOC B. Bonding in Solids

57. Section 10.1 Intermolecular Forces Return to TOC B. Bonding in Solids Stable substances with high melting points Held together by strong forces between ions Ionic Solids

58. Section 10.1 Intermolecular Forces Return to TOC B. Bonding in Solids Fundamental particle is a molecule Melt at relatively low temperatures Held together by weak intermolecular forces Molecular Solids

59. Section 10.1 Intermolecular Forces Return to TOC B. Bonding in Solids Fundamental particle is the atom Properties vary greatly –Group 8 - low melting points –Diamond - very high melting point Atomic Solids

60. Section 10.1 Intermolecular Forces Return to TOC B. Bonding in Solids Metals are held together by nondirectional covalent bonds (called the electron sea model) among the closely packed atoms Video clip – electron sea Bonding in Metals

61. Section 10.1 Intermolecular Forces Return to TOC B. Bonding in Solids Metals form alloys of two types Bonding in Metals –Substitutional – different atoms are substituted for the host metal atoms

62. Section 10.1 Intermolecular Forces Return to TOC B. Bonding in Solids Metals form alloys of two types Bonding in Metals –Interstitial – small atoms are introduced into the “holes” in the metallic structure