1. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 1 Figure 10.1 Schematic Representations of the Three States of Matter

2. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 2 Intermolecular Forces Forces between (rather than within) molecules.  dipole-dipole attraction: molecules with dipoles orient themselves so that “+” and “  ” ends of the dipoles are close to each other. Ô hydrogen bonds: dipole-dipole attraction in which hydrogen is bound to a highly electronegative atom. (F, O, N)

3. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 3 Figure 10.2 Dipole- Dipole Attractions

4. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 4 Figure 10.3 A Water Molecule

5. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 5 Figure 10.4 The Boiling Points of the Covalent Hydrides of the Elements in Groups 4A, 5A, 6A, and 7A

6. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 6 London Dispersion Forces 4 relatively weak forces that exist among noble gas atoms and nonpolar molecules. (Ar, C 8 H 18 ) 4 caused by instantaneous dipole, in which electron distribution becomes asymmetrical. 4 the ease with which electron “cloud” of an atom can be distorted is called polarizability.

7. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 7 Figure 10.5 London Dispersion Forces

8. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 8 Some Properties of a Liquid Surface Tension: The resistance to an increase in its surface area (polar molecules). Capillary Action: Spontaneous rising of a liquid in a narrow tube. Viscosity: Resistance to flow (molecules with large intermolecular forces).

9. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 9 Figure 10.6 Molecules in a Liquid

10. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 10 Types of Solids Crystalline Solids: highly regular arrangement of their components [table salt (NaCl), pyrite (FeS 2 )]. Amorphous solids: considerable disorder in their structures (glass).

11. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 11 Representation of Components in a Crystalline Solid Lattice: A 3-dimensional system of points designating the centers of components (atoms, ions, or molecules) that make up the substance.

12. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 12 Representation of Components in a Crystalline Solid Unit Cell: The smallest repeating unit of the lattice. 4 simple cubic 4 body-centered cubic 4 face-centered cubic

13. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 13 Figure 10.9 Three Cubic Unit Cells and the Correspond ing Lattices

14. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 14 Bragg Equation Used for analysis of crystal structures. n = 2d sin  d = distance between atoms n = an integer = wavelength of the x-rays

15. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 15 Figure 10.10 Interference of Light Rays

16. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 16 Figure 10.11 Diagram to Support the Bragg Equation

17. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 17 Bragg Equation Used for analysis of crystal structures. n = 2d sin  d = distance between atoms n = an integer = wavelength of the x-rays

18. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 18 Types of Crystalline Solids Ionic Solid: contains ions at the points of the lattice that describe the structure of the solid (NaCl). Molecular Solid: discrete covalently bonded molecules at each of its lattice points (sucrose, ice). Atomic Solid: atoms at the lattice points. Three kinds of atomic solids: network, metals, group 18.

19. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 19 Figure 10.12 Examples of Three Types of Crystalline Solids

20. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 20 Packing in Metals Model: Packing uniform, hard spheres to best use available space. This is called closest packing. Each atom has 12 nearest neighbors. 4 hexagonal closest packed (“hcp”) 4 cubic closest packed (“ccp”)

21. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 21 Figure 10.13 The Closest Packing Arrangement of Uniform Spheres

22. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 22 Figure 10.14 Hexagonal Closest Packing

23. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 23 Figure 10.15 Cubic Closest Packing

24. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 24 Figure 10.16 The Indicated Sphere Has 12 Nearest Neighbors

25. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 25 Figure 10.17 The Net Number of Spheres in a Face- Centered Cubic Unit Cell

26. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 26 Bonding Models for Metals Electron Sea Model: A regular array of metal cations awash in a “sea” of electrons, matey. RRRRR. Band (Molecular Orbital) Model: Electrons assumed to travel around metal crystal in MOs formed from valence atomic orbitals of metal atoms.

27. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 27 Figure 10.18 The Electron Sea Model for Metals Postulates a Regular Array of Cations in a “Sea” of Valence Electrons

28. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 28 Figure 10.19 The Molecular Orbital Energy Levels Produced When Various Numbers of Atomic Orbitals Interact

29. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 29 Figure 10.20 The Band Model for Magnesium

30. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 30 Metal Alloys 1. Substitutional Alloy: some metal atoms replaced by others of similar size. brass = Cu/Zn Substances that have a mixture of elements and metallic properties.

31. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 31 Metal Alloys (continued) 2.Interstitial Alloy: Interstices (holes) in closest packed metal structure are occupied by small atoms. steel = iron + carbon 3.Both types: Alloy steels contain a mix of substitutional (Cr, Mo) and interstitial (carbon) alloys.

32. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 32 Figure 10.21 Two Types of Alloys

33. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 33 Network Solids Composed of strong directional covalent bonds that are best viewed as a “giant molecule”. 4 brittle 4 do not conduct heat or electricity 4 carbon, silicon-based graphite, diamond, ceramics, glass

34. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 34 Figure 10.22 The Structures of Diamond and Graphite

35. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 35 Figure 10.23 Partial Representation of the Molecular Orbital Energies in A) Diamond and B) a Typical Metal

36. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 36 Figure 10.24 The p Orbitals in graphite

37. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 37 Figure 10.26 The Structure of Quartz

38. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 38 Figure 10.27 Silicate Anions

39. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 39 Figure 10.28 Two Dimensional Representations of (a) a Quartz Crystal and (b) a Quartz Glass

40. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 40 Semiconductors 4 Conductivity is enhanced by doping with group 3a or group 5a elements. A substance in which some electrons can cross the band gap.

41. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 41 Figure 10.29 Silicon Crystal Doped with (a) Arsenic and (b) Boron

42. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 42 Figure 10.30 Energy Level Diagrams for (a) an n-Type Semiconductor and (b) a p-Type Semiconductor

43. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 43 Figure 10.31 The p-n Junction

44. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 44 Figure 10.33 The Holes that Exist Among Closest Packed Uniform Spheres

45. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 45 Figure 10.34 The Position of Tetrahedral Holes in a Face-Centered Cubic Unit Cell

46. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 46 Figure 10.35 Cubic Closest Packing in NaCl

47. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 47 Vapor Pressure... is the pressure of the vapor present at equilibrium.... is determined principally by the size of the intermolecular forces in the liquid.... increases significantly with temperature. Volatile liquids have high vapor pressures.

48. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 48 Figure 10.36 Behavior of a Liquid in a Closed Container

49. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 49 Figure 10.37 The Rates of Condensation and Evaporation

50. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 50 Figure 10.38 Vapor Pressure

51. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 51 Figure 10.39 The Number of Molecules in a Liquid With a Given Energy Versus Kinetic Energy at Two Temperatures

52. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 52 Figure 10.40 The Vapor Pressure of Water

53. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 53 Figure 10.42 Heating Curve for Water

54. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 54 Melting Point Molecules break loose from lattice points and solid changes to liquid. (Temperature is constant as melting occurs.) vapor pressure of solid = vapor pressure of liquid

55. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 55 Figure 10.43 The Vapor Pressures of Solid and Liquid Water

56. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 56 Figure 10.44 An Apparatus that Allows Solid and Liquid Water to Interact Only Through the Vapor State

57. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 57 Figure 10.45 Water in a Closed System

58. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 58 Figure 10.46 The Supercooling of Water

59. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 59 Boiling Point Constant temperature when added energy is used to vaporize the liquid. vapor pressure of liquid = pressure of surrounding atmosphere

60. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 60 Phase Diagram Represents phases as a function of temperature and pressure. critical temperature: temperature above which the vapor can not be liquefied. critical pressure: pressure required to liquefy AT the critical temperature. critical point: critical temperature and pressure (for water, T c = 374°C and 218 atm).

61. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 61 Figure 10.47 The Phase Diagram for Water

62. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 62 Figure 10.48 Diagrams of Various Heating Experiments

63. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 63 Figure 10.49 The Phase Diagram for Water

64. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 64 Figure 10.52 The Phase Diagram for Carbon Dioxide

65. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 65 Figure 10.50 A Schematic of Two Circuits Connected by a Transistor

66. Copyright©2000 by Houghton Mifflin Company. All rights reserved. 66 Figure 10.51 The Steps for Forming a Transistor in a Crystal of Initially Pure Silicon